RAM question on AN8 ULTRA

Hi, i currently have 2 512ram on my system. And i was thinking of upgrading the ram as my system keeps crashing. So, i was thinking can my system support 2 1gig ram? my system specs are as follows: abit an8 ultra amd 939mb amd athlon64 3000+ socket 939 albatrib geforce 6600GT pci- express 128mb+dvi+tv out im not very good with tech stuffs. so, please tell me if there's any another info u guys need. thanks in advance

Memory

Number of Memory Slots 4 × 184 pin

Memory Standard DDR 400

Maximum Memory Supported 4GB

Channel Supported Dual Channel

Note the RAM is DDR and not DDR2 nor DDR3.

As such it is 184 pin and not 240 pin.


Running an online scan might be the best for finding good upgrades:

http://www.crucial.com/




In order to test whether or not your current issue is indeed RAM you might try running MemTest:

http://www.memtest.org/

Memory

Number of Memory Slots 4 × 184 pin

Memory Standard DDR 400

Maximum Memory Supported 4GB

Channel Supported Dual Channel

Note the RAM is DDR and not DDR2 nor DDR3.

As such it is 184 pin and not 240 pin.


Running an online scan might be the best for finding good upgrades:

http://www.crucial.com/




In order to test whether or not your current issue is indeed RAM you might try running MemTest:

http://www.memtest.org/

So, i did the memtest. and it says "all pass, no faults detected"
so how do i know if it's RAM issues? as in like getting more RAM would solve the problem.

anyway, previously i've been using 2x512 and 2x256 on this machine.
and everything is fine for 2yrs.. till recently, while im playing some online game, my com juz restarted on its own.
and it got into this windows did not startup correctly.A recent hardware or software change might has caused it.
it gave me 4-5 options to choose from - Start normally, last known good configuration, safe mode etc etc.
So i pick accordingly, but it all leads me back to the same "windows did not startup correctly.A recent hardware or software change might has caused it."
i've tried doing the recovery console thingy, but it told me that some file is corrupted or something…
so i did a search on the internet and realise that it could be due to the RAM.
SO i took out the 2x256 ram and everything works!
i manage to get windows started and now im stuck with 2x512 ram and frequent hanging of my windows.

It is not good to be mixing RAM sizes, speeds, or manufacturers, especially in a dual channel motherboard. If you want to run 4 sticks they should be all 4 identical in size, speed, and manufacturer.