Help with DDR RAM

I recently purchased a 1.4 ghz ddr athlon pc, with 256MB DDR ram. So, because RAM is so cheap these days, i thought i'd whack on another 256. So i purchased the ram, made sure it was identical to the other, and installed it. However, on start up, it does the memory check, and says i have the full 512mbram, but once the windows ME screen appears, everything goes dark, and nothing works. I am at a complete loss at what to do. Any ideas?

Other info: O/S = windows ME
gfx = 64mb geforce mx
ASUS DDR mobo
SB live soundcard

thanks a lot, i have checked through the mobo guide, didnt reveal anything i didnt already know. One thing i did do earlier was swapping over the original card with the new one, i.e. so they were arranged differently. This made the PC beep like hell until i switched it off and swapped the cards back so that the original is on the left (slot 0). Do i need to check anything in the bios? In the bios it says i have 512mbram, which really annoys me considering the damn thing wont load windows. Thanks for your help, i certainly appreciate it.

But it will/did work with just 256mb of ram right?

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Silly question for you, did you make sure you push the dimms in all the way? have to push firmly until the white clips are locked in. Check that voltage for the ram is 2.5v, not default but 2.5v.

Have you tried one stick at a time to see if one is faulty?

Try looking in bios under advanced features or something, what you are looking for is a default setting/restore for the ram, if not probablly easier to just reset system bios defaults. This will reset any ram turbo settings.

How many Dimm slots are there?

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Ok here are the settings in bios for memory.
Ph limit 8
Idle limit 8
Trc timing value 5
Trp timing value 2
Tras timing value 2
Trcd Timing value 2
Cas latency 2

.Cas latency is the one that makes the difference.

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did u try putting the new one that u recieved in by itself? It could be faulty (happens).

(knows that 256 works but u might just have left the old one in )

Good to have it all sorted out.

hehe all that explaining for a bad chip.

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