I assembled my new rig last night. I have a few finishing touches to do still. Got a bad stick of memory, Jab-Tech sent me a PCI extension cable instead of an ATX extension cable, and a LG775 bolt kit is in the mail. And, well, possibly an issue with the power supply. Antec Twelve Hundred E8400 P5Q Pro Xigmatek HDT-S1283 2x2GB Corsair XMS2 DDR2-800 DHX Corsair HX620 EVGA GTX 260 Core 216 (bought a 192 but comes up with 216 shaders in GPU-Z) With the side panels still off, I fired up Supreme Commander to behold the beauty of my GTX 260. As soon as I entered a saved game, I heard a subtle buzzing noise, but I wasn't conscious of it until I exited the game and the noise stopped. I fired up SupCom again, entered a game, and the noise came back. I put my cursor over the Exit to Windows button and put my head near the innards of the system. I clicked and the noise stopped. I fired it up yet again and listened very closely to my video card and power supply. I poked the exhaust fans, the fan on the heatsink, and the video card fan with my finger to slow them down to hear if the buzzing changed or stopped. It didn't. I couldn't poke the PSU's fan because of the grill, and it was almost time for bed, but I put my ear right up to it and the noise was prevalent. Does the power supply speed up the fan in relation to the load? I couldn't tell if the fan spun faster when I fired up the game. Today after work I'll try to slow down its fan to see if the noise changes. It isn't a constant buzzing. I haven't installed any other games to test it with, but I put SupCom on High everything with 8x AA. It's running at only 1280x1024 though. Can't be very taxing for a GTX 260, right? People have complained about their HX620 squealing (under load I think). Someone here pointed out a thread on another forum where someone concluded that his Radeon video cards made his HX620 squeal. Maybe NVIDIA makes power supplies buzz? I can't recall any noises from my HX520 in my previous rig. I'm only 99% sure it's the PSU. I'm going to really try to figure out if it's the PSU or the video card.