I have not had any experience with that card but I understand that the 9400 is getting a bit outdated. Currently I run a GT 9800 and these are going for about $99.00. It might be worth taking a second look at a faster card. For a few more dollars than the 9400, you will have a better card. Just my .02 cents.
Also, your 4 gig of RAM...are you running 64 bit?