Vista-Ram issue

[Daveoo]

Hello,
My first post on these boards, could really use some help on this problem.

Basically, windows is only recognizing 1gb of ram out of 3gb i have installed. I just today noticed this, but im guessing its been going on for a little while, can't say exactly how long though, i know for sure it has recognized all 3gb in the past though.

I reformatted recently so im guessing something went wrong after that. (i have all drivers installed from windows update)

Bios settings shows all 3gb installed and working, also running CPUID shows all 3gbs installed. I ran a memory diagnostic and it had no errors, it didn't give me a report like it said it would though, so i can't post that. I've tried pulling all the sticks out, blowing the pc out with air and putting the sticks back in.

System specs:
Windows Vista 32 bit
All 3 1gb chips are DDR2 PC2-4300

Not sure what other info is needed, just let me know what you need to know and ill post it asap. Ty in advance for any help.