Hi! Well, basically i have a BFG 8800GTX, and i RMA'ed it Due to the dreadful nvlddmkm.sys error simply on the desktop! But i then recieved another card from a different batch! and this one is awesome! but now when i game HEAVY like crysis and Flatout UC on full i will get a nvlddmkm.sys BSOD the second any 3d rendering has occured! SO i tried a few hotfixes etc, moved ram and stuff...BUT, i then seen taht overclocking the graphics card has fixed it in some cases (i have done about 1 weeks worth of pure research!) and the second i did i lost visual output...i have overclocked ALOT before. I only overclocked by a low 30mhz of the clock speed (which was 650) and linked to the memory clock too. it reset itself, i restarted the pc (btw i was using rivatuner) and the values went back to standard (650 x 1400), and this time i underclocked it to 550 x 1150...and no crash, no BSOD on crysis full graphics...so i think i am lacking power on the power supply, because its fine all the time even on BF2 full graphics, but crysis just poop, BSOD. May i add that on the old RMA'ed card i played crysis fine, but the clock speeds were 600 x 1200...less than this one from the new batch! and i was using the EXACT same 570watt trust PSU. Im also on the latest drivers 180.xx I just was wondering to see if i should splash out on a 750 watt PSU so i can set the values back to default and not rely totally upon riva tuner! Thanks!