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.
That would be awesome =)
Topic: Avalon ASIC users thread - page 98. (Read 438516 times)
That would be awesome =)
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.
I am running a 1200w supply so I should be fine on the supply side. Going to be switching to 220v as well to gain a bit more efficiency.
I will be running coolant to a radiator outside for watercooling... Unfortunately it has been 105f or 40c for the last month outside. Which is even more reason I want to get the 800+watt this thing produces out of my house!
The main issue I see with cooling is getting the heat from the chips into the heatsink. lastbit's photo earlier show the exact bowing away Im seeing.
As the board heats up you can watch it bow away. I have a clamping solution im working on as well to hold the chips flat against the heatsink.
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 am running a 1200w supply so I should be fine on the supply side. Going to be switching to 220v as well to gain a bit more efficiency.
I will be running coolant to a radiator outside for watercooling... Unfortunately it has been 105f or 40c for the last month outside. Which is even more reason I want to get the 800+watt this thing produces out of my house!
The main issue I see with cooling is getting the heat from the chips into the heatsink. lastbit's photo earlier show the exact bowing away Im seeing.
As the board heats up you can watch it bow away. I have a clamping solution im working on as well to hold the chips flat against the heatsink.
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.
lastbit in terms of what your doing you might want to try this as modding not uploaded all details yet but this s on a batch 2 unit and working out the layout for batch 3 will have details on my website when I get around to it.
Avalon before pictures
Avalon after air flow mods.
Temps before and after more or less the same but not using as much fan power and after mining 24 hours sold this is running nice and cool with oc to 84GH also fans never go above 1800 now so lot better results still doing other mods in time to it to get better air flow. This is with no extra fans added maybe get even better results with some delta fans in but their too noise
Have also taken unit upto 90GH however too many hw% errors however temps solid 50c so not doing too bad. Also added new 860w corsair digital psu working perfect never takes over 730w
Change your diff to 64 on 50btc under settings for miner is probs why you getting too many rejected shares.
Avalon before pictures
Avalon after air flow mods.
Temps before and after more or less the same but not using as much fan power and after mining 24 hours sold this is running nice and cool with oc to 84GH also fans never go above 1800 now so lot better results still doing other mods in time to it to get better air flow. This is with no extra fans added maybe get even better results with some delta fans in but their too noise
Have also taken unit upto 90GH however too many hw% errors however temps solid 50c so not doing too bad. Also added new 860w corsair digital psu working perfect never takes over 730w
Moved from bitparking to 50btc and now I'm constantly getting a lot of Rejected shares at Diff8 
Does anybody have fixed issue like this?
Edit: FW both 20130703 and 20130723
Does anybody have fixed issue like this?
Edit: FW both 20130703 and 20130723
Change your diff to 64 on 50btc under settings for miner is probs why you getting too many rejected shares.
1.3v ... wont that kill the VR? ... like was stated we are at 17-18amps already and it handles 20amps...
From where was the info that it can handle only 20?I dont know where the links to the schematics are anymore... but, it was when I Was reading them. I looked up the main VRM controller chip(fuck if I know what its called) and as per the manufacturers specification the max amps out was like 20amps...
Thanks lastbit!
Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
For 1.3V simple add 47k resistor parallel to R10 (10.5k) - pin2 U1 to GNDIll just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
Unfortunately you have to do for each sub-module 24 or 32
Work on 395MHz 1.2% HW
Indeed 47k in parallel would give ~1280mV, a 11% increase over default.
Assuming chips are able to take also 11% more frequency, you'll need a ~40% more powerful PS, i.e. 1200W for 4 modules.
Not very power efficient
Thanks lastbit!
Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
By module I assume you mean a group of 10 asics with common VR. Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
Each of the big module is connected with 40pin. I believe you can visually and ohmmeter check what pins go to each group and make a custom ribbon cable with only that signals. And of course disconnect the other big modules.
I found module backplane schematics. Indeed each group is connected with 4 signals (2 in, 2 out).
1.3v ... wont that kill the VR? ... like was stated we are at 17-18amps already and it handles 20amps...
From where was the info that it can handle only 20?
1.3v ... wont that kill the VR? ... like was stated we are at 17-18amps already and it handles 20amps...
Thanks lastbit!
Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
For 1.3V simple add 47k resistor parallel to R10 (10.5k) - pin2 U1 to GNDIll just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
Unfortunately you have to do for each sub-module 24 or 32
Work on 395MHz 1.2% HW
Thanks lastbit!
Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
By module I assume you mean a group of 10 asics with common VR. Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
Each of the big module is connected with 40pin. I believe you can visually and ohmmeter check what pins go to each group and make a custom ribbon cable with only that signals. And of course disconnect the other big modules.
Moved from bitparking to 50btc and now I'm constantly getting a lot of Rejected shares at Diff8
Does anybody have fixed issue like this?
Edit: FW both 20130703 and 20130723
Does anybody have fixed issue like this?
Edit: FW both 20130703 and 20130723
How is MHSav calculated? Is it based off valid diff1 work?
Meaning HW errors is already accounted for in MHSav?
By my calculations based on clockspeed, looks like it does account for HW% error.
Also does --avalon-temp clock down regardless if --avalon-auto is used or not? Also, how does that relate to --avalon-freq if setting it to one value... will --avalon-temp still clock down?
MHSav is calculated from valid diff1work and does not count hw errors.Meaning HW errors is already accounted for in MHSav?
By my calculations based on clockspeed, looks like it does account for HW% error.
Also does --avalon-temp clock down regardless if --avalon-auto is used or not? Also, how does that relate to --avalon-freq if setting it to one value... will --avalon-temp still clock down?
Avalon temp works regardless.
Avalon freq is the frequency range that avalon auto will use and ignores temperature unless it is over the optimal range - then it will clock down if the fans can't keep it down.
Thanks lastbit!
Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
Ill just pull the spec sheet for the controller.
Ill probably just drop to a 6k resistor and a 10k pot in series till I can figure out what voltage it takes to get to 400mhz.
Avalon chip spec shows 1.2v typical 1.32 max!
I wonder if I can shut off all of the individual modules except for the one Im working on.
@lastbit.
Have you reworked a VR with the 1.5uH? How much current have you been able to push?
I haven't. I have to solve cooling first. I hope next week.Have you reworked a VR with the 1.5uH? How much current have you been able to push?
Where can I find the schematics for this thing?
Question more difficult than I believed
I have downloaded pdfs from somewhere, I believe it was from github. Unfortunately now I'm only finding this: https://github.com/BitSyncom/avalon-ref. Unfortunately files are in "ALTIUM DESIGNER" format.
R10 is 10.5k, connecting pin2 (FB) of TPS40193 to GND.
@lastbit.
Have you reworked a VR with the 1.5uH? How much current have you been able to push?
I haven't. I have to solve cooling first. I hope next week.Have you reworked a VR with the 1.5uH? How much current have you been able to push?
Im in the process of watercooling mine. Should be done next week as well. I plan on switching out the sense resistors(R10 i believe) on the VR to get to 1.2v.
Where can I find the schematics for this thing?
Does anybody know if it's possible of not to clock each module independently?
@lastbit.
Have you reworked a VR with the 1.5uH? How much current have you been able to push?
I haven't. I have to solve cooling first. I hope next week.Have you reworked a VR with the 1.5uH? How much current have you been able to push?
hmmm, anyone ever see this?:
@lastbit.
Have you reworked a VR with the 1.5uH? How much current have you been able to push?
Have you reworked a VR with the 1.5uH? How much current have you been able to push?
So, here is my first step in overclock batch#3 quest.
I have took out back panel. To much of my surprise, temperature droped 2C !!!
With original fans=100%, @358MHz:
Avalon unit as it came: 24/66/46
Back panel removed: 24/64/45
I have put, as a proof of concept, some pieces of cardboard to force air through fins and at the surface of the boards, especially at the output region of modules. I have also obstructed air path above the modules (where modules cables connect to modules).
No back panel and some cardboard: 24/59/44.
I'd say a success!
Unfortunately this did not help at all regarding frequencies. Still 8%HW errors @375Mhz (like before).
I also think about replacing thermal pad with thermal paste. I have noticed PCB "bulges" between the screws, so I believe thermal contact is less than optimal with the pad:
I have also noticed modules are not parallel. they are slightly tilted, as you can see in the first image. If I would separate the twin connector PCB (for two modules), problem would be solved. I'll do it anyway when I'll work on modules to have only one module stopped at a time. But I believe it's not so important.
I have took out back panel. To much of my surprise, temperature droped 2C !!!
With original fans=100%, @358MHz:
Avalon unit as it came: 24/66/46
Back panel removed: 24/64/45
I have put, as a proof of concept, some pieces of cardboard to force air through fins and at the surface of the boards, especially at the output region of modules. I have also obstructed air path above the modules (where modules cables connect to modules).
No back panel and some cardboard: 24/59/44.
I'd say a success!
Unfortunately this did not help at all regarding frequencies. Still 8%HW errors @375Mhz (like before).
I also think about replacing thermal pad with thermal paste. I have noticed PCB "bulges" between the screws, so I believe thermal contact is less than optimal with the pad:
I have also noticed modules are not parallel. they are slightly tilted, as you can see in the first image. If I would separate the twin connector PCB (for two modules), problem would be solved. I'll do it anyway when I'll work on modules to have only one module stopped at a time. But I believe it's not so important.
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