1) What is new or different since the last time everything worked properly (ie, new hw, new sw, virus, error, etc)?
2) EXACTLY how did you run chkdsk? Please run it as follows: right-click on a command prompt icon and open as administrator. In the command prompt window type: chkdsk /r (then press ENTER). You'll be told the disk is in use and asked if you want to run checkdisk on the next boot. Say yes, exit the command prompt window, and reboot.
3) Please download & install the latest driver for your display adapter (if you're using a desktop, get it from the website of the card's manufacturer - if you're using a laptop, get it from the website of the laptop manufacturer)
4) Install the latest direct-x
5) To check the ram, download memtest (
http://memtest.org/). Burn it to a cd using a dedicated .iso burning utility (
http://www.petri.co.il/how_to_write_iso_files_to_cd.htm), make sure the cd drive is at the top of the boot order in bios, then boot to the newly created cd and run the utility.
Let's see where we are after all of the above is done.