thats great you are trying to base the price on ROI alone, but thats not how the market works right now. I dont want to lose money either.  Thats what anyone values mining stuff at, is potential ROI =P the other people are just dumb enough to buy something overpriced =) well i wont sell myself short, so I will allow supply and demand play its course if there are people willing to pay. but of course =) .. Im just makin a point hehe! Its just funny to me , most miners are willing to spend BTC they will likely never see again ... =/ |
|
|
|
thats great you are trying to base the price on ROI alone, but thats not how the market works right now. I dont want to lose money either. Thats what anyone values mining stuff at, is potential ROI =P the other people are just dumb enough to buy something overpriced =) |
|
|
|
Another miniature buddah.. seriously Mar-14 1765MM? 35 TIMES increase.. Thats what people were saying in march ... hardly anyone thought we'd be at 400-500TH in summer months... and look at what happened... |
|
|
|
Wire and voltage mod preliminary results: Successful!  300Mhz 350Mhz 400Mhz Inductor 1.299v 1.299v 1.299v Middle 1.290v 1.290v 1.288v Bottom 1.291v 1.291v 1.289v chip Before the 16awg wire I was seeing 50mv drop from top to bottom. Only one module of 10 chips was powered up. 400Mhz was perfectly stable. I only ran for 10 minutes due to thermal reasons(my watercooling solution is not active yet) From the Burnin thread SebastianJu is getting 450MHz@1340mV I suspect I should get close to that if the VR can provide the current. Note 400Mhz at 1.3v is a LOT hotter than at 300Mhz!!! if you do this mod you MUST upgrade the stock cooling!!!! Thermal paste on the back of the chips at the MINIMUM!!!!! Very good results, I love the voltage consistency! ... wish someone could test the same mod w/o overvolt and just the wire mod... Im curious to see how much this could improve clocks... If ya could guess, what do you think? 370mhz maybe? |
|
|
|
after 20h I have
[Device Hardware%] => 1.6749
Is this OK?
[Firmware Version] => 20130821
What clock speed? |
|
|
|
|
This is perhaps the most accurate interpretation Ive seen of the specific points made in this article...made to date! This is one well written fantastic peace and is exactly the type of thing that needs to be publicly known by everyone when it comes to bitcoin!
|
|
|
|
whoa that wire mod looks sick...
do you think w/o an overvolt that more consistent voltage will help HW% errors drop and thus a bit higher clock even at stock voltage? cuz that mod seems simple enough.
Yup. JFET transistors act like tiny capacitors when they're closed - the current doesn't actually stop flowing until the capacitor is 'charged'. And of course more volts means faster charge time. On the other hand, of course, it means more heat, and more risk of damaging your chips... Just the wire mod for consistent voltage risks damaging the chips?! ... I would think the more consistent voltage has little / no chance of damage to chips w/ stock cooling.. I know its obvious a mod like 1.34v risks damaging / overheating chips if not properly cooled, but wasnt thinking about doing that. Just the wire mode for tad more clockspeed cuz of the more consistent voltages. I think my cooling setup should handle it fine (5k rpm 250cfm fans) |
|
|
|
Thanks lastbit and GandalfG for the info. I have access to a nice 12ghz oscilloscope and will take noise and ripple measurements of the output of the VR and see if it gets unstable past 20a.
Just took some measurements. At the top of the board closest to the VR im seeing 1.2v at the bottom im seeing 1.15v! Im surprised to see so much of a drop! They must have cheeped out on the amount of copper on the board.
I measure my board with my 100MHz oscilloscope with 1.3V mod and did not see noise on power lines. I check it now after over 10 days mining. About drop: Standby: 1.298V 395MHz: 1.278 on coil VR and nearest capacitor 1.268 first two chip 1.228 last chip. I solder silver-plated wire 0,8mm across one board and check how its help. Have any amps / watts per board power measurement? Also, was this a b2 or b3? Did they change anything on the b3 miner boards? I did not measure amps. It is Avalon clone based on B2 design that I build self. Buy PCB and parts from Strombom. Actually have only 50 chip and patiently wait for supply from Bitsyncom.
50mv drop is horrible!
adding a couple thick wires from the output of the VR to the last chips should help a lot. although the problem could be a return path issue. I dont have my unit in front of me at the moment. I assume the bottom layer is Ground and the top is VCC? There may be an issue with the ground vias/pins not being able to handle the current.
Yes that huge drops are very undesirable. As I stated I solder wire and make measure again. I'm a little surprised that the original B1/B2 have a similar problem. How about B3 machines that have changed design ? I see on one photos hash unit are probably grouped in 4 on one PCB and added thermal sensor on it. Hey, do you have results of the wire mod improvement on voltage? dont recall seeing them... |
|
|
|
whoa that wire mod looks sick...
do you think w/o an overvolt that more consistent voltage will help HW% errors drop and thus a bit higher clock even at stock voltage? cuz that mod seems simple enough.
From what I have read from others on Burnins board thread they are seeing big changes in performance with just a 10mv difference. a 16awg wire should be good for 10a without much voltage drop. it will be a couple of days before I can finish up on the watercooling stuff before I can fire the boards up and take some measurements. Doh! Im anxious .. oh u already did volt mod huh, thats why gotta wait till WC setup is good...? Where were the voltage readouts listed, tried finding them in this thread - didnt find them, was it in the avalon users thread? |
|
|
|
whoa that wire mod looks sick...
do you think w/o an overvolt that more consistent voltage will help HW% errors drop and thus a bit higher clock even at stock voltage? cuz that mod seems simple enough.
Yup. JFET transistors act like tiny capacitors when they're closed - the current doesn't actually stop flowing until the capacitor is 'charged'. And of course more volts means faster charge time. On the other hand, of course, it means more heat, and more risk of damaging your chips... Can you post voltage readings on each chip since doing the wire mod? I wanna know how much its improved as far as being consistent voltage. Any chance you can attempt OC just at stock volts using just the wire mod? My avy, so far, using newest 0820 firmware is capable of 363-364mhz @ 1.7% HW, around temps of under 40C ... at night my avy max temp goes down to less than 35C ... B2 - 3 module |
|
|
|
|
bold considering it will never make that 21BTC back =(
unless diff increase rate slows....and that aint gonna happen =P
|
|
|
|
|
whoa that wire mod looks sick...
do you think w/o an overvolt that more consistent voltage will help HW% errors drop and thus a bit higher clock even at stock voltage? cuz that mod seems simple enough.
|
|
|
|
|
Um..... I dont have the plastic sheet on the "open" side removed. Open meaning the side the modules are NOT mounted too... I dont see how that side serves any purpose in cooling. Now the side the modules are mounted too, functions as a heatsink...yes
Most B2's, if not all came with no plastic on the side that had the modules mounted.
Ive been running my avy for a couple months w/ no adverse affect and the plastic has not melted off...lol, the side mentioned barely gets warm.
|
|
|
|
|
this pool having pool-us.50btc.com issues today?
Its intermittently going dead in cgminer for me ... other pools are fine...
|
|
|
|
|
just noticed 0820 has been posted...whats different in it?
|
|
|
|
|
Show Posts
