See if the Intel DH57JG fits your needs. If you combine it with a Core i3 or Core i5 it makes for a great Mini-ITX Media Center. Check out babgvant's review of it: Missing Remote: Review: Intel DH57JG and Core i3-530. I have a DH57JG + i3-540 in a MiniBox 350M and am very happy with it.
I'm a NVidia fan but the issue with the 9300 is that it does not offer bitstreaming audio and is a little outdated. You don't see as many Mini-ITX boards with the C2D\9300 combo as it was harder cool in that small size.
I use the 9300IE on an M10, no problems and very happy with the setup.
The M10 chassis fan is however noisy and there are limited options for quieter fans as it's 60mm. I've modified a decent 70mm which helps somewhat, although still a bit noisy. You won't however notice it once you're playing something.
Media Centre: Tranquil Passive HTPC | Intel DH67CF - Intel i5 2405S | 8GB Patriot | Intel 40GB SSD | WD Caviar Green 1TB | BGT3595 | Phillips SRT9320
Main Computer: Coolermaster Sileo 500 | Asus Rampage II GENE - Intel i7 965 Extreme | 8GB Corsair | WD VelociRaptor 300GB
Network: QNAP TS419P+ | WD Caviar Black 8TB | Cat6 Wired Network | Belkin Gigabit Router and Switches
mikinhoThe 9300 ... does not offer bitstreaming audio.
The 9300 ... does not offer bitstreaming audio.