How should I cool my 5970 VRMs?

[humanage]

I'm running my 5970 with an Accelero Extreme triple fan cooler, but the VRM temps are VERY high! I've read that this is a common 5970 bottleneck, and I'm trying to lower the temps. I'm now running the card at 1.111v, 910MHz Core/300MHz Memory, and getting 113c,117c,and 115c on the VRMs.
Here's what I've done so far:


I have an 80mm 60 CFM fan blowing air onto the first set of VRMs, and a Scythe fan(40 or so CFM) directing air in the direction. I have a 92mm blue gelid fan blowing onto the other set of VRMs. Finally, I have a Cooler Master fan blowing into the side of the GPU. Any other fan positions I should try? Should I maybe buy some 100+ CFM fans?

[malevolent]

What are vrm temps at stock voltage and core?

[cablepair]

i think 910 is a bit high and excessive

I can get 380 mhash per core at 825

[humanage]

i think 910 is a bit high and excessive

I can get 380 mhash per core at 825

I'm getting 410MH/s on 910MHz.

[MiningBuddy]

What kind of core temps are we looking at?

[OgNasty]

i think 910 is a bit high and excessive

I can get 380 mhash per core at 825

I'm getting 410MH/s on 910MHz.

I can assure you that those extra 30MH/s aren't worth the amount of additional electricity you're buying to run it at those clock speeds.  I can also assure you that at those clock speeds and temperatures, you'll be lucky if those cards are still working a month from now.  So basically, you're destroying your cards and overpaying for electricity for no reason other than turning your room into a sauna.  Turn down the clock speeds or get a water cooling setup.  What you're doing now is insane.

[P4man]

I can assure you that those extra 30MH/s aren't worth the amount of additional electricity you're buying to run it at those clock speeds. 

Higher clocks at equal voltage == better energy efficiency.

@OP: how are you cooling the VRMs? With those small sticky alu fins?
I dont know what the 5970 ref cooler looks like exactly, I know its different, but with a 5870 I had great success using the original baseplate to cool VRMs and ram while using an accelero to keep the GPU cool. The supplied sinks were just not good enough for the VRMs.

Mind you, I did have to dremel the baseplate to clear the accelero heatpipes, but if that doesnt scare you, have a look at the stock cooler and see if it has a baseplate you can use for that purpose. This might be useless advice if the 5970 has a single plate cooling GPUs and VRMs..

If that doesnt work, its time to undervolt the cards and lower your clocks.

[jjiimm_64]

i think 910 is a bit high and excessive

I can get 380 mhash per core at 825

I'm getting 410MH/s on 910MHz.

I never run my 5970's over 820.  most are at 800.  Mine will still be hashing in a year!

The only reason I restarted this rig on the 4th was to upgrade cgminer to the better rpc-api

Code:

cgminer version 2.2.1 - Started: [February 4, 2012, 4:33 pm]    Rig: miner9
(5s):2982.13  (avg): 2966.26 Mh/s  |    Q:690271   A:651964   R:6233   HW:0   E:?%   U:40.52/m
TQ:?   ST:722   SS:?   DW:17127   NB:1600   LW:25420   GF:601   RF:655
Connected to http://gpumax.com:8332 with LP as user ?
Value:
GPU 0:	59.0C	3285RPM 	53% | 	372.7/370.8Mh/s | 	98% |	820Mhz 	300Mhz 	1.05V 	A:81531	R:760	HW:0	U:5.07/m 	I: 7
GPU 1:	61.5C	3285RPM 	53% | 	372.9/370.8Mh/s | 	98% |	820Mhz 	300Mhz 	1.05V 	A:81809	R:733	HW:0	U:5.08/m 	I: 7
GPU 2:	66.5C	3045RPM 	50% | 	372.8/370.8Mh/s | 	98% |	820Mhz 	300Mhz 	1.05V 	A:81030	R:751	HW:0	U:5.04/m 	I: 7
GPU 3:	63.5C	3045RPM 	50% | 	372.8/370.9Mh/s | 	98% |	820Mhz 	300Mhz 	1.05V 	A:81674	R:801	HW:0	U:5.08/m 	I: 7
GPU 4:	63.5C	3125RPM 	50% | 	372.7/370.8Mh/s | 	98% |	820Mhz 	300Mhz 	1.05V 	A:81576	R:769	HW:0	U:5.07/m 	I: 7
GPU 5:	60.5C	3125RPM 	50% | 	372.7/370.8Mh/s | 	98% |	820Mhz 	300Mhz 	1.05V 	A:81537	R:802	HW:0	U:5.07/m 	I: 7
GPU 6:	57.0C	2987RPM 	49% | 	372.8/370.7Mh/s | 	99% |	820Mhz 	300Mhz 	1.05V 	A:81292	R:836	HW:0	U:5.05/m 	I: 7
GPU 7:	59.0C	2987RPM 	49% | 	372.8/370.8Mh/s | 	98% |	820Mhz 	300Mhz 	1.05V 	A:81515	R:781	HW:0	U:5.07/m 	I: 7

even at 810 they get 370, this one is in a warmer spot, hence the higher temps.

Code:

cgminer version 2.2.1 - Started: [February 4, 2012, 4:21 pm]    Rig: miner10
(5s):2967.27  (avg): 2934.61 Mh/s  |    Q:684834   A:646490   R:6218   HW:0   E:?%   U:40.15/m
TQ:?   ST:709   SS:?   DW:18067   NB:1602   LW:25981   GF:681   RF:680
Connected to http://gpumax.com:8332 with LP as user ?
Value:
GPU 0:	72.5C	3081RPM 	50% | 	371.0/357.9Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:79198	R:707	HW:0	U:4.92/m 	I: 7
GPU 1:	69.0C	3081RPM 	50% | 	370.9/368.1Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:80552	R:751	HW:0	U:5.00/m 	I: 7
GPU 2:	73.5C	2949RPM 	48% | 	370.9/368.1Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:81016	R:808	HW:0	U:5.03/m 	I: 7
GPU 3:	73.0C	2947RPM 	48% | 	370.9/368.1Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:81012	R:723	HW:0	U:5.03/m 	I: 7
GPU 4:	72.5C	2639RPM 	44% | 	370.9/368.1Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:81048	R:815	HW:0	U:5.03/m 	I: 7
GPU 5:	73.0C	2639RPM 	44% | 	370.9/368.1Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:81227	R:757	HW:0	U:5.04/m 	I: 7
GPU 6:	73.5C	2747RPM 	49% | 	370.8/368.0Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:80989	R:810	HW:0	U:5.03/m 	I: 7
GPU 7:	68.5C	2749RPM 	49% | 	371.0/368.1Mh/s | 	99% |	810Mhz 	300Mhz 	1.05V 	A:81448	R:847	HW:0	U:5.06/m 	I: 7

.

[humanage]

Alright, got down to 800Mhz Core/ 300MHz memory. I'm getting 49c and 47c on the GPU cores, so that's not a problem.
The VRMs are at 82c/81c//81c for the first core, and 74c/75c/73c on the 2nd core. Lets say I don't raise the voltage above stock, would a high clock speed damage/degrade the card?

[ssateneth]

Alright, got down to 800Mhz Core/ 300MHz memory. I'm getting 49c and 47c on the GPU cores, so that's not a problem.
The VRMs are at 82c/81c//81c for the first core, and 74c/75c/73c on the 2nd core. Lets say I don't raise the voltage above stock, would a high clock speed damage/degrade the card?

Nope, high core speeds won't kill a card.

Temperatures are really the only thing that'll kill a card if you overclock smart. Most overvolting for mining is minor (maybe +0.025 to 0.075 in even the most extreme cases) and won't hurt the card either, anything above is generally overkill for 24/7 and generates too much heat to remain stable at the clock speed you may have aimed at. An example is one of my 5870's is stable at 1100 core and 1.200 volts with temperatures currently around 40c core and 68c VRM since it sits outside in the winter air. It requires more volts to hit a higher clock speed than 1100, but the higher temperature renders the higher speed unstable. I see a lot of gamers use even higher volts of 1.25+, probably because the cards aren't at 100% load with the games they're playing and temperatures are lower as a consequence.

[ace24]

Higher clocks at equal voltage == better energy efficiency.

Well, no. Voltage is only one part of power usage, higher clocked cards use more current than lower clocked cards at the same voltage. That's why overclocked cards get hotter even when not overvolted.

[ssateneth]

Higher clocks at equal voltage == better energy efficiency.

Well, no. Voltage is only one part of power usage, higher clocked cards use more current than lower clocked cards at the same voltage. That's why overclocked cards get hotter even when not overvolted.

No, he's right, when taking the whole computer into the power efficiency picture. 10% more core frequency = 10% more power used (and generally mhash scales linearly with core speed), but the system has a baseline watts, so do some math with some assumed numbers...

100w baseline, 1000w used from video cards doing 2000 mhash. 1.8181 mhash/watt.
Increase core speed by 10% without increasing volts, system is now at...
100w baseline, 1100w used from video cards doing 2200mhash. 1.8333 mhash/watt.

[P4man]

Well, no. Voltage is only one part of power usage, higher clocked cards use more current than lower clocked cards at the same voltage. That's why overclocked cards get hotter even when not overvolted.

Yes, power consumption scales linearly with clockspeed. But performance also scales linearly with clockspeed.
Higher performance at equal MH/W for the cards, means higher efficiency for the overall rig since CPU, MB, RAM, etc remain the same.

Power consumption scales quadratically with voltage. Clockspeed -and  thus performance- does not. Therefore undervolting almost always gives better MH/W, but overclocking is completely sane from an efficiency POV.

[BOARBEAR]

Well, no. Voltage is only one part of power usage, higher clocked cards use more current than lower clocked cards at the same voltage. That's why overclocked cards get hotter even when not overvolted.

Yes, power consumption scales linearly with clockspeed. But performance also scales linearly with clockspeed.
Higher performance at equal MH/W for the cards, means higher efficiency for the overall rig since CPU, MB, RAM, etc remain the same.

Power consumption scales quadratically with voltage. Clockspeed -and  thus performance- does not. Therefore undervolting almost always gives better MH/W, but overclocking is completely sane from an efficiency POV.

Performance does not scale linearly with clock speed at all.  (try 500mhz and 800mhz and you will see)

[P4man]

Performance does not scale linearly with clock speed at all.  (try 500mhz and 800mhz and you will see)

Of course it does. Unless perhaps if you are using SDK 2.6.

[humanage]

I can assure you that those extra 30MH/s aren't worth the amount of additional electricity you're buying to run it at those clock speeds.  I can also assure you that at those clock speeds and temperatures, you'll be lucky if those cards are still working a month from now.  So basically, you're destroying your cards and overpaying for electricity for no reason other than turning your room into a sauna.  Turn down the clock speeds or get a water cooling setup.  What you're doing now is insane.

I pay a fixed power bill, so I'm just trying to squeeze as much power out as I can. Also, I'm hoping to get 890MHz core on 1.112v. With sub-100c VRM temps, would this be okay?

[jjiimm_64]

I can assure you that those extra 30MH/s aren't worth the amount of additional electricity you're buying to run it at those clock speeds.  I can also assure you that at those clock speeds and temperatures, you'll be lucky if those cards are still working a month from now.  So basically, you're destroying your cards and overpaying for electricity for no reason other than turning your room into a sauna.  Turn down the clock speeds or get a water cooling setup.  What you're doing now is insane.

I pay a fixed power bill, so I'm just trying to squeeze as much power out as I can. Also, I'm hoping to get 890MHz core on 1.112v. With sub-100c VRM temps, would this be okay?

maybe you dont realize what the 30Mh extra will get you....

assuming 5% growth of btc, using this calculator http://striketeam.ath.cx/btccalc/btccalc.php
usd exchange: 4.5

Month BTC    USD    Difficulty
1   0.63   2.835   1521061.30173
2   0.57   2.565   1676970.08516
3   0.51   2.295   1848859.51889
4   0.45   2.025   2140286.00056
5   0.4   1.8   2359665.31561
6   0.36   1.62   2601531.01046
7   0.32   1.44   3011597.33599
8   0.29   1.305   3320286.06293
9   0.26   1.17   3660615.38438
10   0.23   1.035   4237619.88434
11   0.21   0.945   4671975.92248
12   0.18   0.81   5150853.45454

 
Total    4.41   19.845      


so after a year of burning up your 5970 for an extra 30Mh, you will make 4 btcs.....if the card lasts a year

[humanage]

maybe you dont realize what the 30Mh extra will get you....

assuming 5% growth of btc, using this calculator http://striketeam.ath.cx/btccalc/btccalc.php
usd exchange: 4.5

Month BTC    USD    Difficulty
1   0.63   2.835   1521061.30173
2   0.57   2.565   1676970.08516
3   0.51   2.295   1848859.51889
4   0.45   2.025   2140286.00056
5   0.4   1.8   2359665.31561
6   0.36   1.62   2601531.01046
7   0.32   1.44   3011597.33599
8   0.29   1.305   3320286.06293
9   0.26   1.17   3660615.38438
10   0.23   1.035   4237619.88434
11   0.21   0.945   4671975.92248
12   0.18   0.81   5150853.45454

 
Total    4.41   19.845      


so after a year of burning up your 5970 for an extra 30Mh, you will make 4 btcs.....if the card lasts a year

I see you point. I'll definitely stay on stock voltage then.

[The-Real-Link]

  I'd also highly advise against tons of overvolting on them.  Like others said, the efficiency may increase at higher core clocks but the power use and heat increase *dramatically* with overvolting.  Tried mine at 900mhz only once.  Power use for two of the cards increased by over 300w on load, VRMs were in the 120s nearly constantly - I could tell as in AB you'd see the core clocks keep throttling back and forth.  Sure you'd get some extra MH but the effort simply isn't worth it IMO.

  Kept mine all around 800-820 range on stock volts and they stay working for the most part exceptionally well and temps are good.  VRMs will still be in the 80s/90s but that's just how it works.  They throttle at 125C though so it's not abnormal for them to be hotter than the cores.

[check_status]

This should be stickied for n00bs to Bitcoin mining, like me, who might attemp to apply gamers tweaks to their setup.
I haven't pulled my 5970 out of its box to run yet and this thread has already helped me out. Sweet.