im not all that knowledgeable about ram so if anyone could help me id appreciate it a lot. i want to buy an extra 512mb of ddr ram on ebay but i dunno if it will be compatible. atm i have 256mb and 128mb ram sticks and they work together well. theyre PC2100/266mhz and i think theyre non-ecc. that's all i know. can someone tell me what will determine if ram will work together. does the ram have to be the same speed? so in my case do they all have to be PC2100/266mhz? what else?

heres a picture of my ram. if anyone can clarify what ram i need it would help a lot. thanks in advance.

http://img210.imageshack.us/img210/6497/ram7qb.jpg

Hey there and welcome to techspot!

Most of the time it is best to use only identical sticks with going with combinations. But as that is not always possible, and identical sticks can be very hard to find most of the time, sometimes you just have to do your best to lower your chances of incompatibility and take a risk.

In your case, if you get another stick of PC2100, there is a good chance it will work. Check with your motherboard maker's website first and see if they have any ram compatibility reports you can look at. Also confirm that your board will work with 256mb sticks.

Good luck!

hi, thanks for the reply. well i have a Dell Dimension 4400 which is a few years old. i cant seem to find any motherboard compatability reports on their site. i think ill just take a safe risk (if you can call it that) and buy a 512mb PC2100 non-ecc stick, as my current RAM is like that, and hope for the best

thanks again and i'll let you know what happens.

oh btw, what's CL2.0 & CL2.5? is there any difference in terms of compatability?