The EeePC 1005HA unfortunately only has 1 slot for RAM which means you have to replace the one it comes with if you wish to upgrade. This is a bit annoying as it is a waste of a 1GB stick of RAM but worth it for the performance gain. These are the details for the RAM:
- 2GB
- PC2 - 5300 or 6400
- 200-pin SODIMM - important as this is laptop sized RAM
- 667 or 800MHz
- The model I bought is a Kingston KVR667D2S5/2G

To install it in the EeePC you must first remove the cover over the RAM slot. You can see at the top of the picture a gold thread - that is what the screw you need to remove goes into. It is a bit worrying when you try and remove the cover as it feels very stiff, but there are just some clips down the sides of the cover which you can ease off - then you are in.
Then you have the RAM and it has a silver bar at the top and the bottom which hold it in. To remove the RAM push these bars away from the RAM and the RAM will pop upwards. Then you can just slide it out and it will be free, then you can put your new bit of RAM in and press it down to click into the silver bars. Make sure the bars line up with the notches in the RAM to check it is fully in otherwise your EeePC will not turn on (as I found out!).
AJ