dnetc516-prerelease clients

[vaughan]

I'm having lots of problems getting the twin GTX275 to run the RC5-72 under Gentoo 64. It seems to run for a little while then the thing just freezes and dies. The PC still runs OK crunching Wep-M2 or whatever its called.

Maybe the box is getting too hot? Ambient is anywhere from 30C to 40C. There are 2x Gigabyte GTX275 GPUs and Intel C2Q 9550 in an Antec 902 case.

[Brucifer]

yep, heat would be my guess. I have a GTX260 that I was getting intermittent results out of. There was just a ton of heat in that box, so I added another fan to the thing so that it was blowing fresh air onto the card. Well it stabilized the card. Another system has a single GTX275. That sucker puts out a lot of heat too, so I can see where a dual would really be a warm one. So you might try adding some fresh air to that puppy and it might help you. I think what happens with them is they get to warm and their thermal protection starts in, acting just like a rev limiter on a car engine and limits the output.

Truthfully, I'm not a fan of the GTX stuff as heat is really an issue with them. I also run a stream 4850. That puts off some heat, but not to the degree that the GTX's do, and it also puts out over double the output of the others. So the stream card is doing much better at using less current.

A respectable output can be gained from the 47xx stream cards, and the current draw is low. I have a 4650 stream which puts out comparable to a 9800GT cuda. Uses a lot less juice, so you don't have to get a hot shot power supply. I'm running 650w power supplies with the GTX275 and GTX260 and those systems are just stripped down windows systems for crunching rc5. If I was a smart duck, I'd just replace both of them with another 4850 and cut the heat and power consumption at least in half.

The bottom line is that for rc5 you just can't beat the ATI/AMD stream cards. Now other projects do much better with cuda than stream I hear. You would really probably do better Vaughan to just pull the dual 275 and put in either a 4850 or4890, and use the 275 for another project or gaming if another cooling fan doesn't do the trick for you.

[Brucifer]

So I noticed that you dumped some rc5 results yesterday. What did you do about the heat issue Vaughan??

[vaughan]

Added a couple of 120mm fans to the CoolerMaster 690 case. Its still very hot so I need to monitor its temps with lm_sensors.

CPU temp: 86 80 77 79 all in deg C

Running WEP M2 on a C2Q9550


Dunno how to get the GPU temps.

[Brucifer]

Nothing like a little heat to warm things up!!