So I got 2 of these from ebay http://www.gigabyte.com/products/product-page.aspx?pid=3354
They don't have voltage control, so they are stuck at 1.088v, but on the plus side, they clock relatively high (1015 and 1035). Unfortunately, one of the 5850's runs about 15C hotter than the other and won't clock as high as a result. From what I can tell, it is not bad contact between GPU and heatsink, but rather bad contact between heatpipes and the fins. I say this because the hot 5850's heatpipes are much hotter to the touch than the cooler 5850.
So... I imagine there is some sort of low melting point metal that joins the heatpipes to the cooling fins. Would it be dangerous to bake the heatsink in an oven in order to reflow the contact points? If not, what temperature should I bake it and and for how long? Also, I have some 60/40 "fine electrical rosin core solder". Would it be possible to use this somehow to increase the amount of contact between the heatpipes and the fins? I don't have any other materials readily available, but I can probably go to the home depot to get something if it would be better suited.
They don't have voltage control, so they are stuck at 1.088v, but on the plus side, they clock relatively high (1015 and 1035). Unfortunately, one of the 5850's runs about 15C hotter than the other and won't clock as high as a result. From what I can tell, it is not bad contact between GPU and heatsink, but rather bad contact between heatpipes and the fins. I say this because the hot 5850's heatpipes are much hotter to the touch than the cooler 5850.
So... I imagine there is some sort of low melting point metal that joins the heatpipes to the cooling fins. Would it be dangerous to bake the heatsink in an oven in order to reflow the contact points? If not, what temperature should I bake it and and for how long? Also, I have some 60/40 "fine electrical rosin core solder". Would it be possible to use this somehow to increase the amount of contact between the heatpipes and the fins? I don't have any other materials readily available, but I can probably go to the home depot to get something if it would be better suited.
The first thing to do would be to leave them alone.
The next thing to do would be to get some arctic silver, clean the GPUs and heatsinks with alcohol and reapply thermal grease, and swap the heat sinks between the cards.
If the problem follows the heatsink, then it might have been manufactured differently or have bad pipes (which have coolant in them to distribute heat).
I get the feeling you didnt read my post entirely. The contact between heatpipes and GPU core is 100% fine. The problem lies with the contact between the heatpipes and the cooling fins. If the heatpipes are hot and the GPU is hot (my situation), then there is good contact between GPU and heatsink. If the heatpipes are cool and the GPU is hot, then there is bad contact between GPU and heatsink. Regreasing the GPU core will do nothing for my problem, because thats not where the problem is, and you cant exactly shove a bunch of arctic silver/noctua/whatever you use into the cooling fins...
In any case, looks like I'll just have to suck it up, or maybe try other BIOS or see if gigabyte has OC software.
I get the feeling you didn't understand my post. You suspect a flaw with the cooler; swap the coolers to confirm the flaw follows a possible bad cooler. My post isn't concerning the grease, just that you need some to do the swap properly and ensure a consistent amount is used.
