Memory Problem.. any ideas

Hello folks, I was wondering if I could use the vast computer knowledge out there to help me with a problem that I am having.

I have a Matsonic MS8157E mobo (I know your saying that you have never heard of this company..lol), Athlon 1800 XP with 512 mb PC2100 mem. I have two 266 FSB slots and two 133 FSB slots.

I currently have one crucial 512 stick in my system. Here is the info on my stick from the crucial website: http://www.crucial.com/store/PartSpecs.asp?imodule=CT6464Z265&cat=RAM

Twice I have addded another 512 mb stick to the other slot and twice my computer has had crashing problems. The first time I bought a centon stick at Circuit City and the second time I ordered the exact stick that I currenlty have from Newegg. I switched them in position both times.

The error was that games (raven shield and bf) suddenly crash to desktop with a grey error window telling me that I do not have enough memory and that I need to allocate more hard drive space for a cache.

???? I place in more memory and get an error telling me that I now dont have enough. Could it be that my dimm slot is damaged? Or am I doing something wrong with this type of memory? Any ideas would be appreciated. I currently am running fine wiht 512 but I only have one more slot and if i want to upgrade then I might be screwed.

I was thinking of upgrading to a Athlon 2600XP cpu (the fastest that my mobo supports) but if my mobo is screwed then I will wait and get a new mobo/cpu set in the future when my 512 mb is too slow.

Thanks ahead of time.

Try going into msconfig>advanced options and see if what your maximum allowable memory is. The value can be changed, but you can occasionaly get errors if it's set lower than the actual amount of memory you have.

Thanks Bingham, I checked and the box is not checked. When I did check it is currently says 512 (which is what I currently have). I should have posted this while I still had the mem. If necessary I will go buy another to try some things out.

Thanks again man