I built my computer about two years ago. At that point, its specs were: mobo: Asus A8N-SLI cpu: AMD Athlon 64 X2 4400+ OS: Windows XP Home Edition SP2 power supply: Antec TP-II 550 GPU: BFG Geforce 7800 GTX OC 256 MB Memory: 1GB Corsair TWINX1024-3200C2 Hard drives: Seagate Barracuda 250GB 7200 RPM SATA (two of them, not in RAID) Case: Lian Li PC-V1200B I put it all together and it worked perfectly fine for about two months. Then, one day, after windows loaded, my mouse cursor started freezing up, everything started responding extremely slowly, and I got a blue screen of death. I restarted it and it worked fine. Since then, it would randomly either work or freeze up a couple minutes after starting up and give me a blue screen of death. It also occassionally froze on the windows xp loading screen, and I also got errors saying that it couldn't detect the disc. This got progressively worse until it wouldn't start up at all. I thought there was a problem with the northbridge on my motherboard, since the northbridge fan had started making loud noises around this point and it seemed to be overheating. I ended up scratching the motherboard slightly while attempting to replace the badly designed fan. Anyway, I ended up having to buy an Asus A8N-SLI Deluxe to replace the mobo. It worked fine for a while, then the fan died again and I ended up having to replace it, successfully this time, with a good heatsink. The new mobo worked fine for a couple months. Then I started getting the same errors again: freezing up after loading windows, random blue screens of death (with many different random error messages), and being unable to detect the hard drive. When it worked, it would great, and when there were errors, it would slow down to a crawl. Eventually it reached a point where windows wouldnt even load any more. I thought there might be an issue with the hard drive controller or something, so I tried moving my hard drives to different SATA ports (there were a total of four ports). Miraculously, after moving my drives to different ports, the computer worked perfectly again. For a few months. Then, every few weeks, I would start getting various errors and BSODs and have to move the hard drives to different ports again. It got progressively worse such that no matter which SATA ports I chose, I would keep getting these errors. Eventually, earlier this summer, my GPU died and I decided to get a new mobo, cpu, GPU, power supply, and memory, hoping this would finally solve my errors once and for all. I also installed an extra side blower to cool down my components even more. New specs: Mobo: Intel BOXD975XBX2KR LGA 775 Intel 975X ATX Intel Motherboard Retail CPU: Intel Core 2 Duo E6600 Conroe 2.4GHz 4M shared L2 Cache LGA 775 Processor Retail GPU: EVGA 640-P2-N821-AR GeForce 8800GTS 640MB 320-bit GDDR3 PCI Express x16 HDCP Video Card - Retail Memory: CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Retail Power Supply: PC Power & Cooling Silencer 750 Quad - Copper EPS12V 750W Continuous @ 40°C (825W Peak) Power Supply Retail Once again, my computer worked perfectly fine, not to mention extremely fast, for a couple months. Then I started getting a new error! I already made a post about it on a different forum a while ago, but no one responded. Anyway, here is the post so that I dont have to write it out all over again: I also started getting: So instead of getting blue screens of death, my computer would give me Delayed Write Failed errors and Unknown Hard Errors and freeze up. Switching SATA ports miraculously still worked, but it kept getting worse and worse. I figured that my main hard drive with windows might be dying, so I replaced it with a 320GB Western Digital (rather than Seagate) hard drive. I formatted it and reinstalled Windows XP Home from scratch. So I now had an extremely clean install of Windows. Once again, my computer worked perfectly for a couple months (no more delayed write failed errors!) but then I started getting yet another new error. One day, my computer started taking about four times as long as normal to start up, and then all sound become extremely choppy. Also, all programs ran kind of choppily and took longer than normal to start up. I tried reinstalling my sound drivers but it was still bad. Then I tried switching my hard drives to different SATA ports, and the problem was miraculously fixed. Then, about a week later, my computer started freezing up randomly and it started happening again. At this point, my main hard drive had been moved from the 1st port to the 3rd port and my 2nd hard drive had been left in the 2nd port. Moving my main hard drive to the 1st port didnt fix the problem, but moving it to the 4th did fix it, at least for now. PLEASE HELP ME! I have no idea what is wrong! I have already replaced nearly all my hardware, Im using a fresh install of windows, and am still getting similar problems. This defies all logic. Is it a software issue or an issue with my hard drive controller? Is it because I am using two hard drives but they arent in RAID? Do I need to install some sort of new driver or firmware? Repeat: Please help, you are my only hope. Thank you!