BSOD with minidumps attached - ntoskrnl.exe errors

I have been having BSOD for the last five months now, off and on. They started almost exclusively when I was playing Skyrim, but in the last week they have been occurring during even basic web browsing or word processing. I have used the BlueScreenView app, which gave me consistent reports of an ntoskrnl.exe error with a stop code of 0x0000001e. The most recent issues have been a variety of stop codes, though: fltmgr.sys / 0x00000024, ataport.sys, win32k.sys, and nfts.sys.

At first I thought it was graphics card / driver related, but after upgrading to a new card and newest driver (and doing a completely clean Windows 7 install), the BSOD returned. Then I thought it might be memory. I ran memtest over night with no errors reported, but bought new RAM any way. Didn’t fix the issue. I’ve tried setting the timing in BIOS based on several suggestions found online; sometimes this would instigate BSOD nearly immediately, but then I thought I’d found a stable timing of 8-8-8-21, 1.5v, 1333Mhz, 2T.

Drivers are all up to date, but I could not update my BIOS, since the BIOS update app for the ASUS is only compatible with a 32 bit OS.

Today the BSOD has been happening nearly every 10 minutes. Even running the SF Diagnostic tool caused it. I’m at my wits end. Any help in finding the culprit would be greatly appreciated. I have a nagging suspicion that my HD (IDE 133) might be having the problem, or maybe my mobo, but that is just a nagging suspicion, with no real knowledge to support it.

My system specs:
OS: Windows 7 64bit Home Premium Svc Pk 1
AV: Trend Micro Titanium Internet Security 2012
Motherboard
Asus M4A79XTD EVO
AMD socket AM3
4x240-pin DIMM slots
1xUltra DMA 133/100/66 for 2 IDE devices
6xSATA 3gb/s

Cpu
AMD Phenom II x4 945
Revision C3
Cache L1: 512KB
L2: 2048kb
L3: 6MB
3000MHz

RAM
Four 2GB sticks, 8GB total memory
G-Skill F3-10666CL8D-4GBHK

GPU
Nvidia GeForce GTX 550 Ti


HDD
C: Drive (programs, my docs)
IDE 133 – 300GB 7200RPM Maxtor