View Full Version : Can anyone tell me why 512mb reads as 256mb RAM?

25-11-2006, 07:30 PM
Can anyone tell me why - after I've installed a couple of 512mb sticks of SD RAM (pc133mhz for an older 400mhz PC) - the PC only sees and utilises 256mb of RAM from each stick? So instead of over 1gB of RAM it reads only 512mB!

25-11-2006, 07:32 PM
Hi Straka. The advice offered to me on an earlier post might help....

Big John
25-11-2006, 07:39 PM
Check your Motherboard specs. It probably can't handle it. I have an old PC that has 768MB in it but it only reads as 512MB as that is all te board can handle.

25-11-2006, 07:41 PM
Different speed RAM, different specs? Motherboard, BIOS, OS.. could be any number of reasons

25-11-2006, 07:55 PM
Interesting. I have a 1ghz Celeron PC currently running windows 98 and it sees and reads 1mB of SD RAM (pc133) - 2x 512mB sticks. Perhaps it has more to do with the mobo/bios - certainly nothing to do with win 98 from my experience.

Billy T
25-11-2006, 10:14 PM
Have you got double sided ram in a MB that only recognises single sided? If it is double sided (chips on both sides of the stick) take one stick out and if it drops to 128MB that might be the answer.

If that does turn out to be the problem, the only solution is to exchange it for single sided sticks.


Billy 8-{)