I'm generally pretty good with computer hardware/software issues but I ran into something that has me stuck...the problem is my dad purchased a set of two 512mb PC3200 DDR 400mhz memory sticks, which I know work...I've tested them in my PC but when placed into his the computer will boot up go throught the BIOS and then display goes blank. Now I know his mobo will support up to 2gb of RAM and he had 512 in there...but it was PC2100...I thought that the PC#### had to with the CPU speed and would only allow the RAM to process as fast as the fastest stick in the system. Basically I don't know what's going on. I swapped his sticks for two of my 512's (PC3200/400) and for some reason it'll show the windows boot screen and then go blank when the logon should be seen. I'm trying to format the computer and when I get it to boot from disc it gives me an error 5### depening on the windows disc I use. I've tried regular XP Home and Pro and also a UA discs, all with the same results. If I put in his old stick it works normally...

Sorry if I wasn't clear or forget something...please help.

Thanks!

(Edit)Motherboard is a cheapo ECS brand, looked in the manual says it'll support the RAM type(400mhz) even DDR2. Hope this helps out a little more.

Edited July 4, 200521 yr by PUnitBabyDaddy

Maybe a bios update will fix the problem???

I doubt that the board will support both DDR and DDR2. The pin configuration is different.

But it sounds to me that you have incompatible RAM, plain and simple. Return the RAM and get some cheap generic RAM. Should work fine in the ECS board.