Anyone know how to interpret POST codes?

[Barry]

I have a very sick computer, and recently bought a PCI/ISA POST (Power On Self Status) code diagnostic card.

A brief description of my problem: my computer runs extremely slowly; windows and applications continually stop responding, sometimes temporarily, often permanently. My Internet browser (IE 6.0) is a waste of time; web pages can take hours to open, if at all, despite my disabling the "Show pictures" option, disabling Windows XP firewall and uninstalling antivirus software. The only operation my PC seems to be able to handle reasonably well is typing in NotePad (typing in MS Word 2002 entails waiting several minutes after every keystroke). I did a clean reinstallation of Windows XP Professional but that made no difference. After running well for about two years, my computer is now practically useless.

The diagnostic card is installed in a PCI or ISA slot; following is an explanation from the manual of what it does:

"When the machine is turned on, the hexadecimal display should show the various POST codes as the system executes (unless it has a rare BIOS that does not display POST codes).
If the machine does not boot, system POST has detected a fatal fault and stopped. The number showing in the hexadecimal display on the Diagnostic Card is the number of the test in which POST failed."

When I boot up the card display quickly runs through a few numbers and stops on 26. This is puzzling to me because my computer does boot up, albeit very slowly, contrary to the above description, which suggests that the card display should only stop at a number if the machine does not boot.

An appendix in the manual lists all POST codes for the main BIOS vendors, and includes the following information:

"Error Code – 26
Award (26)Enable slots 6;Initialize slot 6.Test protected mode exceptions."

I would appreciate very much if someone explained what this means, and perhaps suggest further action I could take to diagnose the problem.

Motherboard: FIC AD11
CPU: AMD Athlon 1.2GB
BIOS: Award ABA46
Internet connection: 56kb/s modem