My card is overheating

[Tactictoe]

I'm pretty sure it just needs new thermal paste but I am not sure if putting new paste in will void my warranty. Can someone verify this for me?

[Störung]

Have you undusted it already a time? I have recently cleaned the fanblades with an earstick cleaner, and blew with some airpressure over it, it gave a difference of 20°c ingame. Some games made my card running near 100°c, after cleaning temps in those games stayed below 80°c.

[Tactictoe]

Yeah I clean my PC out with compressed air and a vac once a week. It's actually blue screening at much lower temps than expected, about 70-80°c. But it runs everything perfect up until then so I am not inclined to blame the card as faulty. Right up until summer I never had a single problem, I have a nice wc loop on my processor with an XSPC RX360 radiator in push/pull, pushing crazy air out the top of my HAF-X case and the big 200mm intake fans it comes with pulling air in the sides and 2 120mm aerocool sharks in the bottom, so ambient temps are acceptable.

It occurs to me perhaps my PSU isn't cutting it...

My system specs:
850 watt CM silent pro 80+ Bronze
Asus Crosshair IV Formula MB
AMD Phenom II 965BE
4GB G.Skill PI
Gigabyte HD6870 1GB OC edition, its pre oc to 915mhz
2x HDD and an SSD
11 Fans!
XSPC cheapy reservoir and pump combo.

I'm at a loss and would rather resolve this problem without having to send the card back if possible, does no one know if the warranty will be void? Most manufacturers consider it general maintenance. They've given this card 3 years but I don't see how its possible to sell a pre-overclocked card and expect the thermal compound to last 3 years. I know even if it doesn't fully solve the problem that temps will drop with application of MX-2 cause it's teh bomb... Or maybe its time to just add the card to my loop...

[Störung]

How warm can your card max get? And when it overheats, doesn't it restart your computer without blue screen normally?
Have you checked Windows problem solver yet?
Or tried this: http://www.resplendence.com/whocrashed

Btw I do think that trying to repair the card yourself will void warranty but I can tell you there is nothing to it disensambling a graphics crad; I just did one of my GTX460 recently because bad fan on it dropped down hit something losing near all the blades. Can't use the card like that and no warranty anymore I think, anyways it's as easy as building a computer for someone with no experience (like myself :p) You'd worry more about it then needed.

And I use 800W CM Silent Pro Gold, no problem running 2 graph cards, 2 ssd+3hdd,... maybe if it went bad but else I think no problem.