If you have not started these are the instructions and information about memtest68+
Next I would like you to run memtest86+. It is quite a long test as it needs to be run for 8 complete passes all at the same time. Please download the test from
Memtest86+ - Advanced Memory Diagnostic Tool. Although the names are similar, this test is much better than memtest86. It needs to be run for 8 complete passes or until you get an error. If you get an error, stop the test. In the link above if you will go down to the middle of the page you can download either the ISO file which needs to be burned to a CD by Windows image burner or any disk image burner you choose. Or you can download the auto installer for USB Flash drives to run it from a flash drive. Whichever you choose, be sure to download the zip file and extract it. Each Pass consists of 10 tests, each pass checks a different thing and each test checks different things. It takes a minimum of 8 passes to completely check the ram, more passes are better. It will take quite a number of hours to do the test, so it is usually better run over night. To run the test, boot from the media you chose and don't press any keys, the test will run automatically and will continue running until you tell it to stop. It will tell you how many passes it has run and how many errors are found. If it finds errors they will show up as red lines at the bottom of the page. It will take somewhere around 9-10 hours to check my computer with 8 GB of ram. If you have more it will take much longer.
Also, exactly what did you mean about check disk not working? Do you mean it did not help or that it would not run?
I would also like you to run a system file checker
Open a elevated command prompt ( click start, type
cmd in the search box,
right click on the cmd entry and select run as administrator) in the black box that opens, copy/paste
sfc /scannow. If you decide to type it, notice the space between the sfc and the /. It is a system file checker which will scan your system files and attempt to correct any missing or corrupt files. What we want are the results to say windows found no integrity violations. If it says files were found but could not be repaired, close the box, reboot and run it again, after opening the administrative command prompt. You may have to reboot and run it three times for it to repair all system files. If it can't repair them after 3 reboots, let us know.
I don't know all the software you have installed, but please download and install
CPUz and post screenshots (
http://www.sevenforums.com/tutorials/9733-screenshots-files-upload-post-seven-forums.html ) of the CPU tab, the Mainboard tab, the Memory tab and the SPD tab. On the SPD tab, you can select each Dimm Slot from a dropdown box in the top left of the screen. We only need the Dimm Slots that are populated with Ram.
I would like you to monitor your CPU and GPU temps constantly and tell me what they are , especially at that 30-45 minute period. I use my Graphics card utility (EVGA Precision X) to monitor GPU temps and
Core Temp for CPU temps. There are other utilities, but I use those. If you need alternative utilities just let me know.