I had a Xenium Ice Solderless/ stock HD and I played the following games on XBL:
Halo 2
CS
NBA 2K5
NFL 2K5
NHL 2K5
College Hoops 2K5
(a few other I can't recalll)
As long as you have your hard drive locked and are playing off the Retail BIOS you will be fine. I have no idea about the big HDs and 2nd HDs and all that- I never got that advanced with my modding.