Have 2 gig in it already and want to put an extra gig in, as Vista 32bit takes up one gig...

Specs...

Q6700 @ 3.20ghz

8800gtx @ 635/1050

2gb 667mhz

Vista Premium 32bit

Will be buying from Crucial, they have a memory selection tool so I can input my xps710 and I get below results, which should be 100% compatible.

http://www.crucial.com/eu/store/listparts.aspx?model=XPS%20710

But which one and will Vista/Dell pc recognize it, or will I have to fiddle with the bios when booting with it for the first time?

This one seems good value, would be a bit stupid to pay €30 for 1 gig of PC 5300?So slow etc

http://www.crucial.com/eu/store/mpartspecs.aspx?mtbpoid=891917F8A5CA7304