That could work. I haven't played with the LS yet, but I would say the key is to get a fan on top of the heat sink and one blowing from the side over those FET heatsinks. Running even a little vornado on mine is keeping things cool.



There's only one fan? Blah, I thought there would be two. Ok.

C

Oh you're going to have a *FUN* time. This is getting more interesting every day.

I just noticed they're doing another Chili board run. $350 or so for the board, you add the chips and the heat sink. Sounds like a "good" deal but I wonder if anyone noticed two things:

1) This thread points out that Jallies can jump from 2 chips to at least six.
2) Butterfly Labs is running a sale on Jallies with delivery in December for $200 on Friday.

You get the board, fan, sink, case, even the power supply. I am really. Really. Really tempted to pick another one up and stick a pair of chips on it. In fact I'm in on at least one; anyone else?

Agreed on this diagnostic. While not running a chili, my jally with 5 chips picked up an extra 1.5gh from a real heat-piped heat sink square on all chips.
C

Looks like a pretty good thing to have if you need to do reballing. I'm split between something like that and a full-bore IR rework station. I can do things with the air tools, but that ability to focus heat down on a single component could be very helpful when I am replacing transistors as small as the little capacitors on the BFL boards.

How many chips do you have to do?

C

Thanks for reporting on this. Real data always helps, I have put three little heat sinks on the bottom of my three hot FETs as well as the top, and both are wicking away a pretty fair amount of heat.

The temp sensor for the board is in the center of the square of 8 hash engines, it does a very good job of watching the temp of those chips but does not do a good job of monitoring outliers like the FETs. Although come to think of it, the little SC box that the jally uses pulls the air from the front, right over the FETs, up through the heat sink, and out the top. Maybe that is why they did that; and putting the fan upside down will cool that center board sensor (which is really not the problem) but will not flow air over (and in the case of the SC60) or under the FETs.

Does anyone with an SC60 have access to a IR temp tool? I am wondering about the temp of those sinks, with the fans going down.

Looking forward to hearing about the repairs.

That is making a nice difference. One of my outstanding questions was why two of the new chips were hashing at 3gh or so while the third was at 4.3gh. With the new sink covering all the chips and wicking away the heat, I am seeing 4.0+ on the two (obviously corner) chips and 4.3 on the inside one.

Very impressive. Moral: If you're going to double your chips, put them on the cross positions so they are all covered by the heat sink. Better yet, get a better heat sink with pipes to remove the heat more efficiently.

This weekend I might try putting mine back in the case and see if it will keep itself cool. Then if I get my chips I'll go for six.

Thanks Inaba!

A note to everyone watching:

I have been in contact with the gentleman/lady/person who is selling chips here on the forum. Apparently he has a limited supply of them, so if you want chips from this source I highly recommend buying them... soon.

https://bitcointalk.org/index.php?topic=236103.0

Kudos to drug5bitz for finding this person. I bought one (in addition to 3 more coming in from another source) so I should be good to go for now.

Edit: AND all the chips are sold again. What the hell is it with me? :-)

C

Well, looks like I am going to Ebay and will be spending another chunk of change for one of these. That's a lot better than searing chips with the flamethrower.

How did you get more flux on the chips? Dump it around the chip and let it wick in?

C

Ok, stupidest auction ever:

http://www.ebay.com/itm/Butterfly-Labs-BFL-Jalapeno-Bitcoin-Miner-ASIC-Works-In-Kansas-City-/301027169857

Summary: Jalapeno for $640.

A jalapeno that BFL probably threw in the garbage. With a NO WARRANTY STAMPED ON THE TOP.

People are so far beyond crazy they have entered stupid-town.

One of them. If there was no crossflow on the bottom heat sinks then that would be problematic. Likewise if the fans just pointed inbound then only half the sink would get cooling, the case provides the tunnel for effective crossflow top and bottom.

Someone needs to send me a blown one of these, I'll post a whole thread on how *not* to nuke your Single. Or something.

Just to clarify, was the case open or completely off? Were the side fans on, how were they blowing?

C

Dropped you an offer, I'm toasting chips to see how far we can push a jally.

If it works, lot of jallies out there...

Interesting. Off to Ebay to buy one; they look like garbage, but why not. :-)

It really only needs 120 degrees C of heat on top to float the chips? Or is that 320C


I am so tickled that this works....

That's about right, now grab a cheap-o IR thermometer and check the temps on those FETs. With 4 it's not a problem, going to 5 starts to push into odd places. I assume this is running with open case, fan down, no sink on the bottom?

Good work!
C

If there is one thing I learned working the dot.com bubble in 2000, it was that it's not possible to lose money on every sale and expect to make it up in volume.

*sigh* I think this may be the secret of what makes rich people rich: People move in dumb herds, and if the herd is grazing on that chunk of grass it's better to be over here eating this chunk that no one knows about because everyone's "following the herd".

Unfortunately this means you have to pass on a lot of things: When I was lending on prosper.com (good lord, the site prospers.org is amazing about this) we would watch as loans got bid well below where any reasonable person could expect to make a profit. Of course all of those people took massive losses when everyone defaulted on their loans. Me, I made a profit of 50 cents on 1,200 invested and felt *exceptionally* smart.

Issue there is the same as mining: The herd is swinging in that direction so you have to look elsewhere. In fact time spent bitching about mining is time not spent finding the next best thing.

Tough lesson.

WK: Thank you. I don't know if you ever sleep or eat, but hopefully you do.

C

By the way, I know people like to jump on BFL a bit, but other miners explode and catch fire as well. Maybe it was their cool marketing, or super success in the FPGA world, but no vendor is a true commodity in the mining world. All this stuff is experimental.

As for ship dates, the forum is full of stuff that never shipped at all.

That said, buying a used 30 or 60 is a bit tricky: If they've been modded you lose any warranty, and they do blow up esp if modded. Jallies seem to be indestructable, but they are underpowered (and I'm doing my best to turn one into a fusion reactor)

C

WTF.f.f.f.f.f.

Answer: People on Ebay are crazy. I should sell my 20gh jally on Ebay for $4,000.

Answer 2: There's a dearth of mining gear, maybe it's because everyone cancelled their orders when difficulty was going up 50% a week or so. That and several big mining things kind of failed to launch.

But really, it's #1: People are fucking nuts. Always have been

Edit. A 30gh unit mining as of Nov 1 on Genesis block will make a little over a thousand worth of bitcoin. That. is. literally. it.

So people are more than nuts, they're crazy.

Close. The copper sink I had came from an IBM x366 system, big ole Pentium XEON chips. I wish I had saved another sink, but you know how it goes.

The surface plate is too big to fit on the back of the board directly because there are 8 little vias to the left of the chips, and those are copper on the bottom. Short out potential. So I initially drilled two dimples in the heat sink, and stuck the jally with the AL plate on it with some cheap-o Radio shack heat sink compound. Worked well, the aluminum heat sink gets *HOT* and it was wicking heat into the plate.

Then I said "Hm", went out to the shed and drilled two holes into it. Removed two fins from the centerline, and ran two screws through it, AL plate, board, crummy AL sink on top. Works *well*.

Then I said "hm hm" and put heat sink compound on both sides of the AL plate (board and sink). IT WICKS A LOT OF HEAT AWAY and solves the heat problem completely. If I got a router and put a channel into the copper plate so it would clear those vias I would just mount it to the whole back of the unit and call it a day.

I don't quite recall the surface size, it might be in the BFL specifications PDF for the little single. Take yours apart and check with a set of calipers, actually you can see the chip outlines on the back so measure it there without removing the heat sink. Go as big as you can, and if possible get it under the FETs on the side over to the CPU board. That's the heat spot.

I'll shoot some better pics this weekend, this little guy is almost a work of art at this point.

C

Looking at some old BFL documents and pictures I am really ready to double-down on the whole "do not overclock your single". The power system is rated for about 100 amps over 8 chips, there is really no room for error. And I double checked some of my notes: When FETs are not all placed in the same location for heat sharing you do get the situation where the current load is split unevenly, which causes one set of FETs to get hotter and source more power till they explode.

Oh as far as water cooling? Forget the top, water cool the bottom of the board. The chips can sink an amazing amount of heat through the board, it's flat and with the exception of a few copper vias pretty perfect for a nice big plate that can cool the chips, the FETs, half of everything. Then just put a normal sink and fan on top and go to town.

C