So here's the story. I bought the following PC from TigerDirect for myself: - eMachines C3060 AMD Sempron 3000+ / 512MB DDR / 160GB HDD / DVD±RW Dual-Layer / CD-ROM / Flash Media Reader / NVIDIA GeForce 4 MX Video / 10/100Mbps LAN / Windows XP Home / Refurbished Desktop PC. I upgraded to 1 GB of RAM, upgraded the power supply to an Antec SmartPower 500W, and installed this video card: XFX GeForce 6600 / 256MB DDR / AGP 8X / Dual DVI / TV Out / Video Card. I bought the following PC for my brother at Newegg: - ABS Awesome V2 30 Athlon 64 3200+ 512MB DDR 160GB NVIDIA GeForce 6150 Windows XP Home - Retail. I upgraded it to 2GB of RAM and installed this video card: XFX PVT42EUDE3 Geforce 6800XT 256MB GDDR3 PCI Express x16 Video Card - Retail My computer would work perfectly, except for random hardlocks whenever I played World of Warcraft. One day it hardlocked, and when I restarted it, it would freeze on the big "e" logo (emachines). To this day, that is all it does now. My brother's computer worked perfectly at his house for months. He brought it over this week (visiting for Thanksgiving), and it worked fine for awhile, until it started to get a sort of BSOD. Something about dumping physical memory or something. Now for some reason it will show the bios screen (manufacturer advertisement, similar to the big "e" on my computer), and then freeze on a black screen. We have the PC's hooked up via KVM switch with my dad's older Gateway running Windows 2000. They are also hooked up on the same hub. Could this have anything to do with it? Could my dad's computer be infecting ours? My problem is I have no idea where to start. I don't know why my brother's computer worked just fine until he brought it over here. Any help would be GREATLY appreciated. I feel like I've thrown over 2 grand down the toilet.