I finished building my new PC last week. Specs: Antec Nine Hundred Two case MSI P55-GD80 mobo 8 GB Corsair Dominator RAM Intel i5-750 CPU Cooler Master Hyper 212 Plus Corsair HX750 PSU Windows 7 64-Bit Home Premium When I originally built this computer I re-used my GeForce 9600GT from my old computer. I was not really happy about doing that because it was giving me problems in my old computer (freezes and reboots when I tried to run graphics intensive programs). Almost immediately (I built the computer last Monday night), I started having new problems with the card/drivers. Let me note here that I had successfully completed installing Windows 7 and it was running fine (except for the video problems). I was getting frequent freeze ups and then it would "unfreeze" and give me the error message that "Display driver NVIDIA Windows Kernel Mode Driver, version 191.07 stopped responding..." I was also getting infrequent total freeze-ups, reboots and the occasional BSOD (referencing nvlddmkm). Sometimes I would go hours without any of this happening, sometimes it would "pause", give the "Display driver NVIDIA..." message several times in a couple of minutes. I researched the error messages and found lots and lots and LOTS of hits - but no real answer. I had (more than) enough RAM, the CPU was cool enough (28 degrees C) and I had updated to the latest drivers. Since I suspected that the card was somehow damaged, I ordered a new radeon 5850 (VisionTek). However, later that evening (this would be last Thursday), the "pauses" and reboots reached a crescendo and I had a new problem on my hands. It simply wouldn't boot into Windows. I would get the BIOS to post, and then Windows would start to load and then... ...well, not much after that. Sometimes it simply froze with a blank screen and sometimes it rebooted (by itself). I tried to get into Windows safe mode (pressing F8), but it wouldn't do it. I also tried booting from my Windows 7 install DVD, but I got the "Windows files loading" screen, and then it rebooted and the whole process started over. In fact, when I tried to boot from the DVD AGAIN, I didn't even get the "Windows files loading." So I shut down the computer and waited for the new card. It arrived today, I anxiously and excitedly installed it, turned the computer on and... ...the same thing. I was actually able to (once) get the Windows safe mode menu, selected to boot into Windows safe mode, watched it load files and then...it rebooted by itself without going into windows. I've been unable to get the safe mode menu since. I should also mention that I am not seeing any error messages. I either get a blank screen or it reboots. Again, it posts the BIOS, goes to load Windows and then either freezes with a blank screen or reboots by itself. I am not able to get the Windows safe mode menu to come up (I did once, but was unable to successfully load Windows safe mode). I am not able to boot off of the Windows 7 install DVD. Back when I was really knowledgeable about Windows (back all those years ago in Windows 95 and Windows 98), I would get around this problem by booting off an emergency boot floppy, reformatting the hard drive and reinstalling windows. Sad to say, I don't know how to accomplish that same thing nowadays. I do have a laptop (which I'm using to type this up) and it has a CD/DVD burner, so I could burn a emergency boot CD/DVD, but I'm not sure where to go to get that done (and the laptop uses Vista). I'm hoping that it's simply a really, really messed up windows display driver and that a reinstall would work. But I'm not positive that is the problem. I have no reason at this time to suspect any hardware problems, but that doesn't mean there isn't. Any/all help here would be greatly appreciated.