Assuming that the memory is properly seated, and recognized correctly by the bios, I would start here to check for problem memory. hcidesign.com/memtest/download.html
Ok, here's my problem:
I have a Biostar M7VIG Pro motherboard
(http://www.biostar-usa.com/mbdetails.asp?model=m7vig+pro). I just replaced the AMD Duron 1.2 ghz CPU I had with an AMD AthlonXP 1800+. My system memory is two 512meg SDRAM modules. The system bus is set to 100mhz. My OS is Windows XP Home.
When I had the Duron installed, if I attempted to change the bus speed to 133mhz, the computer would just beep at me when I turned it on. I found out that this Duron did not support 133mhz bus speed.
When I upgraded to the Athlon and switched the bus speed to 133mhz via a jumper, the computer appeared to be loading just fine, but just before it got to the user login screen (I have 2 profiles - 1 for me and 1 for my wife), it freezes up at the Windows XP logo screen (the little green bar that is moving from left to right stops moving). This is with my 1 gig of SDR RAM.
I attempted to switch out my two 512meg SDR modules for two 1 gig DDR modules when I upgraded to the Athlon (I have 2 SDR slots and 2 DDR slots). When I boot up (remember, we're at 100mhz bus speed), I get a ton of memory errors and unstable performance to the point of the computer rebooting itself. These are the results with the Duron too.
The DDR modules have "1GB DDR333 Module 16C G37 Y34" printed on a label on them and have what I can only assume to be a part number (since they both have the same number) under the barcode on the memory's label: 00020040628.
So here are my questions - can you think of any reason why the computer wouldn't accept the 133mhz bus speed (this is the more important of the two)? Can you think of any reasons for the erratic behavior of the memory?

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