Computer becomes extremely unstable every 2-3 months seemingly at random.

[Ikana]

My system is extremely slow, applications constantly hang, explorer.exe crashed every couple of hours, and the whole system is generally unstable. This happens seemingly at random every couple of months, and then I have to re-install windows and replace nearly 1TB worth of data only to have it repeat the process again. I'm wondering why this happens, and what I need to do to fix it.

I'm running windows 7 home premium, i've checked the pc for malware, i've ran the memory diagnostic tool countless times, i've used the command "sfc /scannow" both from my Windows 7 DVD's repair function and from within windows on an elevated CMD prompt (I can't remove the "repair pending" flag for the DVD so it's useless), I've run CHKDSK about 5 times (each time an enormous string of orphaned files are deleted over the course of an hour) , and I've even had my 1 TB HDD checked for hardware failure at the shop down the street.

Boot time has more than quadrupled, once earlier today it stalled on the little splash image for my MOBO (I'm not familiar with all the technical jargon) for about an hour before resuming normal boot procedures. this literally happens like clockwork every 3-5 months. seemingly overnight my computer goes from a midrange gaming pc that runs quite well, to a sluggish disaster reminiscent of an old laptop circa 2001. Just browsing the internet causes my web browser to hang, I am plagued by requests to end application processes and I have no idea how to remedy this.

Can somebody just tell me what the CAUSE is? in about 3 hours I'm going to reformat my HDD and reinstall windows 7 for the 3rd time this year. This is extremely draining and for the life of me I cannot fathom why it happens.

I'm running windows 7 home premium with 16 GB ram, Phenom II 965 black quad core @ 3.4GHZ, and a gtx 550TI, everything is running at stock speeds and i've made NO changes to any system files aside from Explorer.exe (for custom themes, which I have reverted back to defaults)

Sorry for the jumbled mess, my mind is going haywire and I am super stressed over having to reinstall nearly 650 GB worth of games and move another 20 GB of pictures of my two sons to an external HD on a system breathing its last breath.

 

[clutchc]

maybe your registry is clogged with errors and the system is bogged down with junk files and resource wasting card. Try CCleaner. Do the Clean and Registry portions both. Run them until they come back clean. See if that helps any.
http://www.piriform.com/ccleaner

 

[Ikana]

Posting off my phone now, I ran those utilities multiple times, but nothing changed, I ran dskchk all night last night (twice actually); now windows boots to a black screen with a mouse cursor. It is completely unresponsive. Winre startup repaid detects no problem, and as at other times, I've been looking for a way to run sfc /scannow for about 2 hours now to no avail.

 

[clutchc]

The next thing I'd suspect would be a failing PSU. Btw, I just sent back a MB that had similar problems, though. It wouldn't complete the Win7 installation. It would crash at the first re-boot with a black screen and white pointer every time. Hopefully that isn't your issue.

 

[Ikana]

It's been quite a while since I posted on this thread, and I'm not trying to necro it back to life, but It was actually my 1TB HDD failing, very slowly. I ended up reinstalling the OS like 3 times in a year. All my files were slowly corrupting little by little. I changed out my HDD and everything has been stable since. Just a heads up if anybody is searching the same problem up in some search engine and it leads them here.