Continuously returning BSOD, BSODs randomly, CPU related?

Recently had problems with BSODs. At first, I managed to figure out it was the CPU overheating, so I bought a new heatsync, and that fixed the bluescreens. Since then, they started again, and I ended up buying a new CPU, which again, fixed it. It then bluescreened again, and I checked the thermal paste, reapplied it, and it fixed it. It should be noted that even though I replaced the thermal paste, the temps always displayed below 40 degrees Celsius, so I'm not sure why this has fixed it. Bluescreens stopped for 4-6 weeks inbetween changing cooler and reapplying thermal paste.

My thoughts are now that there's not proper contact between the heatsync and the CPU, or it's my motherboard, but I'd like someone to tell me what they find in the dump files.

Thank you.

Notes:
CPU: AMD Phenom II x4 965 (The one before this was a 955)
GPU: GTX 460 1GB (I've tried swapping this for an old ATI HD 3870 512MB, didn't fix BSOD)
Mobo: ASUS M4N75TD
RAM: 8GB Corsair PC3-10700H 1600 MHz (Running at 1333 MHz because BSOD keeps resetting it, I previously had 4GB Corsair 1333 MHz which was replaced with this to try and fix BSODs)
HDD: Samsung Spinpoint F4 1TB (Have replaced this with an older HDD during bluescreens, did not fix)

As you can see, I have replaced every element of hardware in my PC except the motherboard so far. Only fiddling with the CPU has succeeded in giving me a break.

BSODs can often cause PC not to boot without RAM check button being pressed.
BSODs have caused it to complain that there is a corrupt boot file.

Welcome aboard, voltlight!

► You need to install service pack 1

► Run Disc Check:

1. Reseat the sata and power.
2. Run chkdsk /f/r, following the option two of the tutorial Disk Check
3. Seatool for dos: SeaTools | Seagate download
   Burn it in a blank cd. boot from the CD, click on "Accept", wait for it to finish detecting the drives, then in the upper left corner select "Basic Tests", then select "Long Test" and let it run.

► update the network driver.
First, download the network card driver from manufactuer's website. (nVidia nForce I guess).
Then reinstall the driver:

1. Click the Start Button, type "devmgmt.msc" (without quotation marks) in the Start Menu Search box and press Enter.
2. Double click to expand "Network adaptors".
3. Right click your network card and click Uninstall.
4. Check "Delete driver software for this device" check box, click OK.
5. Restart the computer
6. If windows does not auto configure the appropriate drivers at startup, install the downloaded one manually.

► Free up the startup.

1. Click on the Start button
2. Type “msconfig (without quotes), click the resulting link. It will open the System Configuration window.
3. Select the “Startup” tab.
4. Deselect all items other than the antivirus.
5. Apply > OK
6. Accept the restart.

Let us know the results.