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Author Topic: [CLOSED] ASICMiner Prisma 1.4th/s - 1.47 BTC  (Read 49906 times)
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philipma1957
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November 13, 2014, 01:45:00 AM
 #621

okay running 2 boards   poolside reports 690gh

minera has a low number


 two fans running handles out two boards  no worries.  




I had to modify minera to report the correct total hash rate for prismas. This modification was made after your unit shipped.

To get the latest code perform the following steps

shell in and change directory to /var/www/minera

git fetch --all
git reset --hard origin/master


it is running pretty well  .

  is shell in the same as ssh.  I am more of a gear head then a coder.  I would be very likely to kill my sd card.

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CrazyGuy (OP)
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November 13, 2014, 01:46:40 AM
 #622

That is solid advice. Please remember, you are running a 1200 watt device with exposed circuit boards .Two things I would highly reccomend not doing.:
Touching the exposed circuit boards, or putting them in close proximity to conductive material.


Also, I have just paid out compensation to batch 1-5 for the late shipment from ASICMiner. Thank you to all that participated in this group buy.

ASICPuppy.net ASIC Mining Hardware and Accessories - Compac F in stock!
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November 13, 2014, 01:48:53 AM
 #623


it is running pretty well  .

  is shell in the same as ssh.  I am more of a gear head then a coder.  I would be very likely to kill my sd card.

Yes, ssh

You can do it straight from the user interface by clicking on system->open terminal. Or use putty or some other ssh client.

ASICPuppy.net ASIC Mining Hardware and Accessories - Compac F in stock!
philipma1957
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November 13, 2014, 03:49:24 AM
Last edit: November 13, 2014, 04:15:26 AM by philipma1957
 #624

hey is it possible to get 1600gh with this? never mind it dropped to 1500  3.5% error 40 C due to garage door opened a bit. watts are 1244 at freq and 1500 gh or .8293 watts a gh at the plug





watts at 1244

top of the line psu evga 1600 watts platinum




opened garage back door let in some cool fall air.  fan brings in cold air



a second fan a delta ebay 9 bucks .   and I spaced the long tube since we don't want our long hot tubes popping from the heat do we.





one fan for the middle burnout issue



let the hash crank up

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November 13, 2014, 05:02:59 AM
 #625

as for the second person talking about burning up a tube ..   both had the same thing in common close to a solid metal plate.    a  power surge then an arc to the plate then pop.    as a point of safety do no rest your tube miners near metal plates.  use other safer ways to stack them
  it is common sense an open set of ciruits .25 inches away from a metal plate = danger.

look at the tube design .  I told more then one person do not use it on metal. I used wood.  now on this the long tube I rest it on


I apologize for not being clear.

I purchased sheet metal from Home Depot 3 days ago, in anticipation of the NEW RMA REPLACEMENT Prismas -- because I wanted to make sure there was *something* fireproof and projectile-proof beneath the miner this time.  (If metal is a bad choice, then I made a bad choice.  But that's not the point.)

The fires do *not* have this in common -- because my fire was 2 weeks ago, not 2 days ago.  When my unit caught on fire, it was sitting on a piece of wire shelving, which was in kind of a "sandwich" -- two pieces of wire shelving with some "slices" of thick PVC pipe between them.  In other words, the Prismas were on NON-CONDUCTIVE, plastic-coated wire shelving -- suspended a good 3 inches above the MDF/whatever shelf below.

The fire was *not* caused by an arc -- there is no metal near any of my miners -- it's actulally all stacked next to the wall, because I was hoping to try to use it to PROTECT in the future against this kind of thing -- and if that's stupid (which apparently it is) then so be it, but please understand the fire I discussed involved *zero* chance for any "arcing" of any sort -- unless it occured within/between mining boards.  No metal was present and more than adequate airflow was available to the bottom unit.

I will try to post pictures tomorrow--apologies, its' late in my timezone and I need to be up early.  But I am eager to "make amends" as I told Crazyguy in a series of questions he just asked over PM, which I gave him full permission to quote or paraphrase as he likes....whatever needs to happen in order to make sure nobody else is potentially put in danger.

Again, and I apologize for beating a dead horse but I regret sending the wrong message in my previous post: The first guy's post, where he shows the metal plate beneath his miner... whether it's a "best practice" to use metal or not, the fact remains:  that metal plate saved his house from burning down, assuming the flames happened when he was asleep or not at home.  It deflected / blocked the exploding capacitors and other components that (in my case) simply bounced through the giant holes in the wire shelving and were hot enough to set a slice of PVC pipe on fire...along with parts of the shelf itself.

It is not a "metal arcing issue" that caused this damage -- though that might be a valid concern, I don't claim to know otherwise.  It's just *not* the reason this particular "blast pattern" happened.  By all means, use ceramic tiles to protect your shelving and not metal -- I couldn't find any light (and not super expensive) tiles myself, and I didn't want to triple the weight of my shelves with the cheaper heavy tiles...  And other devices (like the Antminers) have a metal exterior shell, so I thought it would be possible to "box in" one of the Prismas to keep other things safe.  Maybe this was a stupid idea.  Unfortunately, stupid ideas made *after* the fire don't really serve to explain why the fire happened in the first place.

I would write more, but like I said I just wrote it all to Crazyguy who in theory was asking so he could share the info with you guys.  -- oh, and please don't misunderstand the "tone of voice" in my message here, I'm trying to type quickly and sometimes I come across like an ass or argumentative, and I assure phillip, you I don't disagree with your statement that metal might not be the best firepoof material to use -- I just wanted to clear up the misunderstanding that led you to believe there was any metal, anywhere near the fire that I experienced last month.

I hope that makes more sense this time?  Crazyguy can you help me explain this better?  (I'm tired as fuck and possibly not making any sense to anybody...hopefully CG can swoop in for the rescue and put this into normal human words that people can understand ...sorry for the confusing first post.)
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November 13, 2014, 05:16:04 AM
 #626

as for the second person talking about burning up a tube ..   both had the same thing in common close to a solid metal plate.    a  power surge then an arc to the plate then pop.    as a point of safety do no rest your tube miners near metal plates.  use other safer ways to stack them
  it is common sense an open set of ciruits .25 inches away from a metal plate = danger.

look at the tube design .  I told more then one person do not use it on metal. I used wood.  now on this the long tube I rest it on


I apologize for not being clear.

I purchased sheet metal from Home Depot 3 days ago, in anticipation of the NEW RMA REPLACEMENT Prismas -- because I wanted to make sure there was *something* fireproof and projectile-proof beneath the miner this time.  (If metal is a bad choice, then I made a bad choice.  But that's not the point.)

The fires do *not* have this in common -- because my fire was 2 weeks ago, not 2 days ago.  When my unit caught on fire, it was sitting on a piece of wire shelving, which was in kind of a "sandwich" -- two pieces of wire shelving with some "slices" of thick PVC pipe between them.  In other words, the Prismas were on NON-CONDUCTIVE, plastic-coated wire shelving -- suspended a good 3 inches above the MDF/whatever shelf below.

The fire was *not* caused by an arc -- there is no metal near any of my miners -- it's actulally all stacked next to the wall, because I was hoping to try to use it to PROTECT in the future against this kind of thing -- and if that's stupid (which apparently it is) then so be it, but please understand the fire I discussed involved *zero* chance for any "arcing" of any sort -- unless it occured within/between mining boards.  No metal was present and more than adequate airflow was available to the bottom unit.

I will try to post pictures tomorrow--apologies, its' late in my timezone and I need to be up early.  But I am eager to "make amends" as I told Crazyguy in a series of questions he just asked over PM, which I gave him full permission to quote or paraphrase as he likes....whatever needs to happen in order to make sure nobody else is potentially put in danger.

Again, and I apologize for beating a dead horse but I regret sending the wrong message in my previous post: The first guy's post, where he shows the metal plate beneath his miner... whether it's a "best practice" to use metal or not, the fact remains:   that metal plate saved his house from burning down, assuming the flames happened when he was asleep or not at home.  It deflected / blocked the exploding capacitors and other components that (in my case) simply bounced through the giant holes in the wire shelving and were hot enough to set a slice of PVC pipe on fire...along with parts of the shelf itself.

It is not a "metal arcing issue" that caused this damage -- though that might be a valid concern, I don't claim to know otherwise.  It's just *not* the reason this particular "blast pattern" happened.  By all means, use ceramic tiles to protect your shelving and not metal -- I couldn't find any light (and not super expensive) tiles myself, and I didn't want to triple the weight of my shelves with the cheaper heavy tiles...  And other devices (like the Antminers) have a metal exterior shell, so I thought it would be possible to "box in" one of the Prismas to keep other things safe.  Maybe this was a stupid idea.  Unfortunately, stupid ideas made *after* the fire don't really serve to explain why the fire happened in the first place.

I would write more, but like I said I just wrote it all to Crazyguy who in theory was asking so he could share the info with you guys.  -- oh, and please don't misunderstand the "tone of voice" in my message here, I'm trying to type quickly and sometimes I come across like an ass or argumentative, and I assure phillip, you I don't disagree with your statement that metal might not be the best firepoof material to use -- I just wanted to clear up the misunderstanding that led you to believe there was any metal, anywhere near the fire that I experienced last month.

I hope that makes more sense this time?  Crazyguy can you help me explain this better?  (I'm tired as fuck and possibly not making any sense to anybody...hopefully CG can swoop in for the rescue and put this into normal human words that people can understand ...sorry for the confusing first post.)

good follow up thanks.  I am also a bit tired. but exploding caps can happen.  I will look about for examples and post links.

Mining is fun.  burnt up gear is not.   but at least it was not this bad.



It was said to be 5MW facility......




pre fire
http://storage.googleapis.com/spond_public/images/cowboyminer%20wall%20of%20SP30.jpg

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November 13, 2014, 05:21:11 AM
 #627

I did contact Mr InvalidSnack to get more details on what happened to his Prisma in an effort to prevent this from happening to anyone else. The response was very long, and I have yet to parse it all, but one thing I did gather is that the units were stacked on top of each other with a bumper in between each handle. Here are some tips I gave him to follow upon receipt of his RMA unit from Canary/AM.

1) Don't stack the units. I think it's possible the arc may have been board to board in Mr Snack's case.
2) Lay the units out on a non-conductive material with at least half a foot in between each unit
3) Make sure your units are in a cool environment.

As always, tighten heatsink screws upon receipt and visually inspect each board for damage during shipment. Use an IR gun to measure board temperature and notify your seller if you are seeing anything unacceptable.

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November 13, 2014, 05:31:45 AM
 #628

"Mister InvalidSnack" ...lol. 

At least you sent me to bed with a smile on my face, Mr. CrazyGuy.  (Or do you prefer Dr CrazyGuy, PhD?) 

And as for the 5 MW facility --  Phillip you read my mind, I've literally spent the last few days reading about that and looking at the pictures you referenced and going..."well, I only managed to burn up 2/3 prismas, and the antminers were safe...so it LITERALLY could be much much worse."  But this wasn't supposed to be a pity party for me -- I was (perhaps prematurely) trying to alert people to a possible dangerous flaw ... and as I told Mr. CrazyGuy, it's entirely possible I just saw that picture of the other users' "blast pattern" and thought "oh fuck, you've gone and done it now...you never mentioned this and you know his post is going to say something about 'losing seven family members in the blaze,'"  -- in other words , guilt might have turned me into Chicken Little.  It's too late for me to really tell -- need to sleep on this.


But regardless, I would still strongly suggest people "keep an eye" on these miners.  Mine worked fine for 3 days.  No irregular temperature readings anywhere.  (Well, it was probably "irregular" about the time the fire was eating everything...but you get my point.)  I followed Dogie's guide so every screw was tightened, checked every cap to see if it was wobbly -- so , just, "be mindful of that middle area, and keep checking it for more than a few days before you start assuming everything's fine." 

There, those are my adjusted, far more reasonable "suggestions" for users.  Off to sleep now -- if I wake up and realize I'm a moron and embarrassed myself for no reason, I will go back and remove the more "excitable" language from my previous posts...because I never meant to cause a panic or fuss.  G'Night folks.

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November 13, 2014, 06:07:23 AM
Last edit: November 13, 2014, 06:22:43 AM by helipotte
 #629

Arcing is not possible in the senerio.  The voltages are WAY to low. You would need hundreds of volts or even thousands to jump even a small amount.

http://en.wikipedia.org/wiki/Paschen's_law

This was current runaway.  These chips are most likely a "chained" design used to obtain maximum efficiency.  If one chip in the series "chain" shorts internally, it can

cause a great increase in current through the other chips in the chain thus causing the temperature to rise suddenly and dramatically.  This would literally set them on fire!

Somewhere on here I have seen a picture of a heavily burned "one string miner" that used Bitfury chips.  These use 14 chips and run directly off the 12Vdc feed in series.  

So if one ship shorts, it starts an overcurrent condition that very quickly pops all of the others.
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November 13, 2014, 08:01:06 AM
 #630

I agree, 12v is unlikely to arc over this distance. I just measured where the miner was and the burnt area was about 1.7" above the metal plate. For the record, the metal plate was a last minute decision purely because of seeing the cowboy miner incident.

This is the one place that a arc may have occurred. It's the backside of the board but I can't tell if it was caused by the fire or if it caused the fire.


I did tighten all screws before putting the miner into service and it was running (unstable on a be controller) for a few days before the incident. I also didn't see any missing caps before installation but I cannot find the one missing cap anywhere. From the looks of the board it either fell off between tightening the screws and installing the unit or came off with the heat and disappeared somewhere. All that is visible now is it's solder pads. CrazyGuy and AM are taking care of me warranty wise, no complaints there.

If anyone's interested in the chain of events, I found 15 GPU's offline and no prisma boards showing up on the be controller which wasn't all that uncommon. I went out to see what happened and could smell the all too familiar burnt electronics smell however, it was somewhat faint due to the high airflow of the area. I found a 240v breaker popped, couldn't figure out where the smell was from so I reset it hoping for just another well done GPU and checked to see what was still working. That's when I took the screenshots of the one board with 0 hash rate. After that I powered down both prismas and found the damage hiding underneath one.

Also for those interested CrazyGuys minera image works great on a B+ RPi.

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November 13, 2014, 11:46:36 AM
Last edit: November 13, 2014, 12:12:18 PM by philipma1957
 #631

Well it is a lot of heat and current in a small spot. I mentioned arcing since the metal plate look like it had a welding burn.

Fact is it is an open design with a downward board using a lot of power.  be careful guys.

I am getting a solid 1440 on the site it is mining on = mmpool.org

using 1244 watts

I designed a better bottom cooling fan. the psu  has shorting protection and is on a gfci circuit.

shout out to the cap poppers what were the psu's on your gear.


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November 13, 2014, 01:47:02 PM
 #632

The one thing I did notice is that these are not enclosed like the Antminers S3, I have an idea for those of you running Prisma to add a layer of safety. Perhaps you could find an old screen and screen in your miner. This way the air could flow, yet any exploding caps would be contained. I have a screen door I will use above the unit, while I continue to test my miner.

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November 13, 2014, 03:16:20 PM
 #633

how many PRIMAS can be daisy chained per controller ?
how many can be chained per wart port on controller ?
thank you !
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November 13, 2014, 03:22:29 PM
Last edit: November 13, 2014, 03:45:13 PM by InvalidSnack
 #634

Arcing is not possible in the senerio.  The voltages are WAY to low. You would need hundreds of volts or even thousands to jump even a small amount.

http://en.wikipedia.org/wiki/Paschen's_law

This was current runaway.  These chips are most likely a "chained" design used to obtain maximum efficiency.  If one chip in the series "chain" shorts internally, it can

cause a great increase in current through the other chips in the chain thus causing the temperature to rise suddenly and dramatically.  This would literally set them on fire!

Somewhere on here I have seen a picture of a heavily burned "one string miner" that used Bitfury chips.  These use 14 chips and run directly off the 12Vdc feed in series. 

So if one ship shorts, it starts an overcurrent condition that very quickly pops all of the others.

Thank you for taking the time to explain the concept -- I was familiar with "thermal runaway" and "runaway brides" but not "current runaway."  So this was very educational for me, so thanks for posting it. 

That said, the explanation (above) strikes me so far as the most likely cause...in both fires. I'm basing this not just on "looks" but also on the fact that I recall Asicminer informing shareholders (last week maybe?) of a "Chip Popping" problem that had plagued the BE200 chip, causing failures for various OEMs --  so please correct me if  I'm way off base, but is it possible this "chip popping" could trigger the current runaway you described?

And if that *is* true, then (not trying to cause a panic, just asking the question) -- if there's no known way to identify chips with this defect, and they can run for several days/weeks before they "pop" -- is there any way a regular user (without access to absurdly advanced tools etc) could detect or otherwise know if their unit is at risk?  Wouldn't that mean (to some degree) that all Prismas are at risk for this kind of behavior?


BTW: Please note, I am not trying to push an agenda -- my 2 RMA Prismas are arriving today, and I still have one running (the one that wasn't damaged by the fire) so I'm not trying to worry people or discourage new sales or otherwise hurt ASICMiner.  I honestly just don't know the answer to the questions above, and they seem significant, so I thought I'd ask.  Not a fanboy, not a hater.  Just a miner. Smiley

EDIT:  One other question:  I had all my miners connected via the USB/UART connectors.  But I realize I could have "daisy chained" them together...  This is probably a dumb question but -- when you daisy chain boards, is it kind of like "extending the one string" ... meaning, could a chip pop on one board and then just follow that "string" back from one board to another and another, damaging more than one board (or more than one Prisma)?  That's my main question -- because if daisy chaining makes it possible for ONE popped chip to potentially damage everything that's connected to it, it seems to me like it might be safer to just connect each prisma to a USB hub (rather than chain them together and the connect the last one via USB).  Or is that just such an unlikely scenario that it's not worth worrying about?
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November 13, 2014, 03:29:03 PM
 #635

Minera up and running on a RPI B+ 32 GB memory card with no problems with the image from Crazyguy. I have to thank you Crazyguy for not only making this a great GB for us but for also going that extra mile and then some for me especially. If anyone was ever on the fence about doing any deals or participating in any GB with Crazyguy you really would be doing yourself a disservice if you hesitated in any way whatsoever. Thank you Crazyguy for the refund that you pulled out of your own pocket for all of is because of delayed shipping. Now has anyone been able to get  http://www.mobileminerapp.com up and running yet with this image? That's the only thing I'm hung up on right now. Thanks again Crazyguy
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November 13, 2014, 03:37:20 PM
 #636

how many PRIMAS can be daisy chained per controller ?
how many can be chained per wart port on controller ?
thank you !

anyone ?
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November 13, 2014, 03:39:27 PM
 #637

The one thing I did notice is that these are not enclosed like the Antminers S3, I have an idea for those of you running Prisma to add a layer of safety. Perhaps you could find an old screen and screen in your miner. This way the air could flow, yet any exploding caps would be contained. I have a screen door I will use above the unit, while I continue to test my miner.

Hmm, that's really not a bad idea.  (Assuming a hot cap couldn't just melt its way through the mesh -- screen doors are pretty thin stuff, right?  

But that's the easiest and cheapest idea I've heard so far...a lot better than buying $50 of sheet metal and having to return it to Home Depot, with what I assume my excuse will be: "I'm sorry I bought this but I needed nonmetallic...sheet metal.  So this won't work.  Because it's metal." Smiley


Quote from: phil
Shout out to the cap poppers what were the psu's on your gear.

Two IBM/Delta DPS-2000BB server PSUs, operating in current-share mode (so two 2000W PSUs acting as one big 4000W PSU, which should have been more than plenty for the 3 Prismas, IMO).   I should point out that in my case, no circuits blew -- until I threw the breaker and killed the subpanel that feeds my mining stuff.  It was just happily mining and burning along...and as I told CrazyGuy, I noticed (just because I was near my laptop at the time) that cgminer didn't show any errors or unusual activity when the alarm went off.  (No, I don't expect cgminer to somehow say "look out the board is on fire!" -- but I would have expected melted burning charred exploding chips to ...you know...throw the occasional HW error, lol.)

And I take offense at the term "Cap Popper."  I demand you call us "People who through no fault of their own became victims of cap popping phenomena" ... nah just call it whatever, I'm kidding of course.
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November 13, 2014, 04:05:46 PM
Last edit: November 13, 2014, 04:18:33 PM by mrpark
 #638

Here are some more bright ideas. If you go to home depot you can buy very inexpensive wire shelves and put them under your miner (this one is tan, but they have metal color ones). I may actually elevate this more with a few bricks... You can also bend out the metal on the outsides to raise up the Prisma to get more air underneath, especially if you have fans on the side of the miner. I put my miner on concrete, there is some plastic next to the miner in this photo and also some Blue Max waterproofing (which works great by the way) But I will put a server case door (thin metal) on that side(not too close of course!)

Perhaps with the metal bent out like this, we could make a screen frame. I also bought aluminum L shaped framing material from home depot.




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philipma1957
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November 13, 2014, 04:08:46 PM
 #639

The one thing I did notice is that these are not enclosed like the Antminers S3, I have an idea for those of you running Prisma to add a layer of safety. Perhaps you could find an old screen and screen in your miner. This way the air could flow, yet any exploding caps would be contained. I have a screen door I will use above the unit, while I continue to test my miner.

Hmm, that's really not a bad idea.  (Assuming a hot cap couldn't just melt its way through the mesh -- screen doors are pretty thin stuff, right?  

But that's the easiest and cheapest idea I've heard so far...a lot better than buying $50 of sheet metal and having to return it to Home Depot, with what I assume my excuse will be: "I'm sorry I bought this but I needed nonmetallic...sheet metal.  So this won't work.  Because it's metal." Smiley


Quote from: phil
Shout out to the cap poppers what were the psu's on your gear.

Two IBM/Delta DPS-2000BB server PSUs, operating in current-share mode (so two 2000W PSUs acting as one big 4000W PSU, which should have been more than plenty for the 3 Prismas, IMO).   I should point out that in my case, no circuits blew -- until I threw the breaker and killed the subpanel that feeds my mining stuff.  It was just happily mining and burning along...and as I told CrazyGuy, I noticed (just because I was near my laptop at the time) that cgminer didn't show any errors or unusual activity when the alarm went off.  (No, I don't expect cgminer to somehow say "look out the board is on fire!" -- but I would have expected melted burning charred exploding chips to ...you know...throw the occasional HW error, lol.)

And I take offense at the term "Cap Popper."  I demand you call us "People who through no fault of their own became victims of cap popping phenomena" ... nah just call it whatever, I'm kidding of course.

 making lite of it since no one has been hurt.  

I think I see a problem with using your psu setup if 1 unit goes bad and sucks down a lot of power it is sucking on 4000 watts since it can access both 2000 watt psu's.  In my case I am attached to a 1600 watt psu   the evga 1600 p2  if my unit goes bad it only can access 1600 watts to suck in.

 So I am thinking  no one should use 1 pair of 1000 watt psu's or larger with these.

 ie  if you use 2 psu's  use a pair of 750 watters  both on the same power circuit    thus if the unit fucks up it can only access 1 power circuit and 2x  750 watt psu's

It may be the flaw in the design is if 1 chip weakens    the units will pull more  watts then it needs if it is there and available.

 thus  having 2 x 2000 watt psu's attached  the unit tossed thousands of extra watts at the bad chip to make it hash and popped a cap.

Thanks  to you for  letting us know you had 2 x 2000 psu's .  




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November 13, 2014, 11:06:07 PM
 #640

I'm gonna be setting up some Prismas to host in the next day or two, probably on DPS2K PSUs. Definitely not in load-balanced, which shouldn't be necessary since these boards all have isolated 12V lines. A pair of Prismas shouldn't quite max out a DPS2K, maybe 110% rated. It wouldn't take much of a short to run up to OCP (about 120% rated). Hopefully we don't test that hypothesis with a "live-fire" experiment.

Thanks for the info on what's been going on.

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