Clean the gpu die with some solvent.
Apply something good like Artic Silver 5.
Did that to all my 5870's now they run at 68C with fan at 70%
Out of my 10 5870's I was shocked to find that 4 of them had barely any paste, and what was there was flaky and dry.
Completely agree with this. I have a 5870 and 2 5830's and removing the heatsink and putting new, better paste on helped immensely. Also, if you can add some airflow, it doesnt hurt. I have an open air 5870, running on one "OK" fan (other fan completely seized) with a small fan blowing on it. OC settings are 950/300, I get ~430 out of it, and temps stay between 70-75.
i've got one of those junk gigabytes with the 2 fan combo, one fan blew out... i left the shroud there and ziptied a 120mm directly above the opening of where the 2nd fan was, it ran all day at 980/195 (about 440-445 mhash) and max it got to on Friday was 67oC. well, that system only has 2 cards in it (1 card --empty pci-e slot---1 card, basically because that ziptied 120mm makes it take up about 3 slots) and there's also a honeywell floor fan blowing into it, but during the day it's 100oF + ambient in there too..... well, maybe a bit under that today... high temp was 95o
oh, the second card was running a bit cooler too, maybe 100% from the lower ambient temps, but maybe some from that 120mm too
Hahahaha, man have you been peeking in my basement? Almost the same exact thing here. Have a fan blowing on my Gigabyte 5870 with the one seized fan. Strapped a Kingwin 80,mm to the side with the downed fan. I am using an extender on it, and running it open air, so its actually sitting upright. Keeps it around 71c. On the same board I have an XFX 5830 whos fan seized, so removed it and the shroud, and strapped a 120mm to the front of it. It stays about 60c.