Hello all, this is my first time posting here because I'm at my wits' end. I am a PC technician by trade and recently a friend of mine brought his PC in for an upgrade. We replaced his HDD, PSU, GPU and OS, his previous spec was as follows: AMD Phenom 9500 Quad Core 2.20 GHz 4GB Corsair DDR2 800MHz RAM ASUS M3A Mobo Seagate 250GB IDE HDD Gigabyte 9600GT GPU 'No name' 450W PSU Windows XP Home The new spec of the system after upgrade is as follows: AMD Phenom 9500 Quad Core 2.20 GHz 4GB Corsair DDR2 800MHz RAM ASUS M3A Mobo Seagate 750GB SATA HDD Gigabyte GTX 660 GPU Antec HCG-620M PSU Windows 7 Home Premium 64bit The problem comes in as follows: he only really likes to play Dota 2, however before the upgrade the game would run at around 35-40fps, after the upgrade it goes down to around 20fps even on minimum settings. Now I know that there are many such reports of Dota 2 under-performing on decently specced PCs but when I run 3D mark Vantage it gets a graphics score of 12k (Edit: CPU score of 5200). This score seems extremely low especially since tomshardware and other sites suggest that the 660GTX should be scoring around 24k.... Diablo 3 also runs at around 40-50fps on medium settings, this too seems way under what this GPU should be putting out. Is the CPU creating such a massive bottleneck here or is it the mobo? I've swapped out everything besides the mobo and CPU and I'm running out of ideas. Also its very difficult to find an AM2 socket mobo these days so he'll have to buy a new mobo and CPU and I'll look like a douche because I said that he won't need a new mobo yet (very stupid on my part I know). If anyone has some helpful input I would greatly appreciate it.