Thanks for the advice Bloodwych, it still crashes in the workbench enviroment so I will try some of the other stuff later today.
Enjoying the extra ram too much and end up just playing WHD load games all the time! Must get that registered asap
Edit - Update:
On closer inspection there is a jumper to enable either one or both memory banks meaning I can run it as a 4mb card, then as you would expect I can use the PCMCIA with no problems
Now time to play some more games!