temperature limit

I have overclocked mine to GPU Clock: 801 MHz , Memory 1200 MHz, Shader 2002. is that a good overclock for this gpu or can i push it more further?
 
I would back down the memory to 1150 and then max out your GPU until there's no artifacting, provided it is below thresh hold under max load and 100% fan speed.
 
The thing is my card came overclocked at GPU Clock: 756, Memory 1150 MHz, and Shader 1890 MHz. Right now there is no artifacts that I found using atitool keeping my it at test for 1 hour. Also my fan runs at 80% all the time and in that one hour of artifact test my card never went above 65 C. Also is it fine to keep my fan at 100 percent all time? Because it sounds like it would break if i kept it on 100 percent for too long lol, I don't mind the noise at all but just wondering.
 
It says Delta of 398498 on 298 pixel in ati tools, does that mean its telling me i got artifacts. Also my screen freezes and after few minutes start working again. Also one more question would raising North Bridge voltage would help in overclocking my GPU?
 
Even taking the memory to 1150 and raising my gpu clock to 850 i still get artifacts and my screen freezes. I guess 800 gpu clock is the limit for my gpu.
 
uhmm i would say not... usually if you cant see the artifacts it should be k anywho...dont you officious ppl out there quote me on it tho.
 
you can increase the 9800gtx memory much higher something like 2400(1200) because it uses the 0.8ns DDR3 which is stated to run at 2400 by default. i even seem some review OCed it to 2600mhz.
 
Ok, Im having problems even though i am running my card on those settings, when i play Crysis my game works for like 10 second then freezes on me and then start working again for another 10 seconds and freezes and then later on nvidia drivers fail. I am thinking that drivers 177.79 aren't very good.