Hi,
I've got an Asus P5E-VM HDMI...
Your title asks for the best mATX atm, not the best board for a HTPC, and from my personal experience, this is the best mATX board right now, but not the best HTPC board
There's some issue with VDroop but there is a pencil mod and you have to be extremely unlucky to get a board that the pencil mod doesn't work on (I'm quite possibly the only person on the internet that it didn't work for
)
I've got it running nicely with a 1600MHz FSB (Northbridge at default voltage) and an E2180 clocked at 3.2GHz.
The BIOS is great, there are lots of options for overclocking, far more then I'd expected there to be.
You do need RAM that'll run 1:1 for overclocking though.
I never really bothered testing the onboard graphics because they don't really work above an FSB of 1333...
But anyway, the onboard graphics aren't important because Intel's driver support for the X3500 graphics in the G35 chipset are appalling anyway afaik (no DX10 support, even though the hardware is compatible).
I read somewhere that RAID doesn't work on this board, but I've never tried so I can't advise on that...
Also, some guy got it working with an FSB of 2116MHz... which makes it incredibly awesome for a mATX board
Look Here
I'll edit this if I think of anything else noteworthy
Banjo