Macs can be very Fussy about RAM...
You can use these Links to check which RAM is suitable for your Mac...
It is Important to get the Correct and Matching RAM
Those sites also have videos on how to Install RAM should you need it....
how to i get more memory on my 10.5.8 as i want to install snow leopard
Have you checked that your Mac meets the System Requirements for Snow Leopard...
Snow Leopard Tech Specs > http://support.apple.com/kb/SP575
Hi - yes, it's a MaBook. The Hardward Overview looks like this (and I'm sure it means more to you than it does to me) thanks for your help
Model Name: MacBook
Model Identifier: MacBook5,2
Processor Name: Intel Core 2 Duo
Processor Speed: 2.13 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 3 MB
Memory: 2 GB
Bus Speed: 1.07 GHz
Boot ROM Version: MB52.0088.B05
SMC Version (system): 1.38f5
Serial Number (system): W8*******9GU
Hardware UUID: 23912CE3-E138-5964-A8A2-0382BF4917E8
Sudden Motion Sensor:
<Personal Information Edited by Host>
Your Macbook will recognize up to 6 GB RAM. Follow AnaMusic's recommendations for RAM vendors.
Installation of Snow Leopard will require the following disk:
Your Macbook is capable of running ALL current OSXs, including Mavericks.