my 6600GT runs at about 45 degrees celcius, I'm not sure what the maximum temps i can go to or how far i can push my GPU. Also could people please suggest some good OCing software, thanks
yes 70-80 under load is normal.
use coolbits or tweaked drivers that have coolbits in it to do your OC'ing.
if youve got the AGP version like mine its stock at 500/900 and will easy OC to around 575/1000 just by using the Auto Detect feature.