Advice: Onboard x300 vs 6200 PCI-E

Hi All

I have this motherboard:

http://www.kustompcs.co.uk/acatalog/info_5577.html

I got it mass cheap and will be using it for a HTPC. I now also have 1gb RAM, CPU etc and an XFX 6200 128mb

My question is: would it be ok using the onboard GPU (x300) or will I notice a huge difference with the 6200? Thje machine will be used for general HTPC stuff such as DVD playing, encoding etc

Possible be used on a High Res PC monitor at times too (2405FPW).

Any ideas?:)