Windows 7: Frequent lockups, CHKDSK, BSOD

Help me before I throw my computer out the window.

I have a similar common problem as I noticed a lot of other people have regarding frequent pausing/lockups for about 30 seconds at a time. They're most common when I'm doing something like ripping a DVD, watching a movie, or playing video games, but they also occur just when I'm surfing and have a torrent running.

After several months of that crap, my computer started rebooting into CHKDSK and recovering all kinds of issues. Every once in a while it escalates into a full on BSOD. The latest one (this morning) was related to msrpc.sys



A few weeks ago I did a clean reformat and reinstall of everything. The problems became less severe than the frequent BSODs I had been getting, but the lockups and CHKDSK came back within a few hours. Western Digital's SMART program seems to think the hard drive is perfectly fine. I did some other things people suggested like turning off Windows update, but it hasn't made any difference for me. Prime95 runs fine. My temperatures all seem normal, like 30s C for most things other than the video card (~50-60C between idle and gaming) and the CPU (39-50). I haven't noticed a trend between system heat and freezing/BSOD.

My machine:
Windows 7 Professional x64 (legal copy)
Asus P5Q SE/R
Intel E7400 @2.8GHz (used to overclock it, but it hasn't made a difference in these problems)
4GB OCZ SLI-ready RAM (DDR2 6400)
EVGA 9600GSO 512mb
Western Digital 640GB Caviar Green
Lite-On DVD burner
450W power supply

All of this hardware was bought & built over the summer 2009.

My plan/questions:
1) Replace the hard drive. Is is possible that this is because of the slow-spinning Caviar Green drive?
2) Replace the power supply. Is 450W too low for my setup?
3) Replace RAM?

Thanks for any suggestions/help.

edit: computer froze while running the tool

SF Diagnostic Tool

Ironically my computer froze while running this program. It said "Data error - cyclic redundancy check."

That's an error I get frequently whenever my computer freezes while running various programs, especially when burning or ripping a DVD.

I suspect that it's a bad hard drive - but don't buy another one based on this.

Try the free, bootable tests here:

It's still under warranty with WD so I can swap it out for free.

I will run your programs, though. Thanks for the help