jgaffney is your 1.2 ghz a core, a MD or a hybrid. I think it should do hd fine if its a MD, but for a core or hybrid every thing read leads towards ups 2's or a 3 ghz. You didn't mention how much ram, but it seems that for HD you need 1 gig in a core and 512 mb in a MD. A hybrid would probably benefit from more but mds and core don't seem to show an improvement from any more ram then listed even for HD. Not that they need an improvement they seem fine with the above. I'll be testing this out in a couple weeks with the same tuner that u have, trying a 3.0ghz for a core only and 1.1 ghz for a md, both intel and using the ram listed above.
Shaun