Run hard drive diagnostics: http://www.tacktech....ay.cfm?ttid=287
Make sure, you select tool, which is appropriate for the brand of your hard drive.
Depending on the program, it'll create bootable floppy, or bootable CD.
If downloaded file is of .iso type, use ImgBurn: http://www.imgburn.com/ to burn .iso file to a CD (select "Write image file to disc" option), and make the CD bootable.
NOTE. If your hard drive is made by Toshiba, unfortunately, you're out of luck, because Toshiba doesn't provide any diagnostic tool.
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A. If you have more than one RAM module installed, try starting computer with one RAM stick at a time.
NOTE Keep in mind, the manual check listed above is always superior to the software check, listed below. DO NOT proceed with memtest, if you can go with option A
B. If you have only one RAM stick installed...
...run memtest...
1. Download - Pre-Compiled Bootable ISO (.zip)
2. Unzip downloaded memtest86+-2.11.iso.zip file.
3. Inside, you'll find memtest86+-2.11.iso file.
4. Download, and install ImgBurn: http://www.imgburn.com/
5. Insert blank CD into your CD drive.
6. Open ImgBurn, and click on Write image file to disc
7. Click on Browse for a file... icon:
8. Locate memtest86+-2.11.iso file, and click Open button.
9. Click on ImgBurn green arrow to start burning bootable memtest86 CD:
10. Once the CD is created, boot from it, and memtest will automatically start to run.
The running program will look something like this depending on the size and number of ram modules installed:
It's recommended to run 5-6 passes. Each pass contains very same 8 tests.
This will show the progress of the test. It can take a while. Be patient, or leave it running overnight.
The following image is the test results area:
The most important item here is the “errors” line. If you see ANY errors, even one, most likely, you have bad RAM.