Trying to upgrade my RAM on an older laptop

[Binky1]

I'm trying to upgrade my RAM on an older Presario Laptop, model 2545US.  I bought two 1GB 266MHz RAM sticks and installed them, but obviously the computer doesn't support either the speed or the size.....the sceen just stays black...

It came with two 256K 133MHz sticks, so it's obviously pretty slow. 

What is the most memory/speed this old laptop will support? 

~Binky

[Paul_Tikkanen]

Hi:

I would use the Crucial memory advisor to find out what memory your PC can run. You can either use the drop-down menus to select make, model etc of your PC or you can download the little application to automatically scan your PC and report what memory you can upgrade to.

http://www.crucial.com/

Paul

[Huffer]

On that series you are limited to 1 gig of total RAM or 2 x 512. The memory you need is original laptop DDR (not DDR2 or DDR3) and it uses PC2100 also known as DDR266 SO-DIMM memory. I also seem to recall that with a BIOS upgrade it can run DDR333 memory. You can install DDR333 memory anyway and worst case, it will downclock to 266. DDR333 is more widely available and usually cheaper. The confusing thing is that some DDR modules say 133 mhz which is technically the speed it runs at, but since it is double data rate it is effectively 266. (It is technical but the processor "fetches" data from the memory twice on each stroke of the clock hence double data rate). So the "266" you put in it is the same speed as the "133" you originally had in it. 2 x 1 gig sticks of laptop DDR must have set you back a litle bit of money! Get 2 x 512 mb sticks of the same kind of memory and you will be good to go.

Here is a link to the Manual for that series:

Your Manual