New (recycled) Server Win7?

[dgeezer]

I am currently running my SageTV setup with an HD100 and an HD200 on my 2 TVs with a headless server. The server is an old desktop Emachines with a single core Athlon 64, 4 various sized hard drives, and only 512mb of ram. It runs XP and works fine most of the time. I seem to occasionally run up against having enough ram. The SageTV service consumes at least half my ram most of the time. I have 2 tuners in the server, an HVR-1600 and a PVR-150 to record analogue cable and an HDHomerun which records QAM.

The server runs SageTV and Comskip and pretty much nothing else. I don't use Playon since I can't transcode the video on this machine. I would like to be able to access Hulu and Pandora and retire my Boxee pc.

My options are to add some ram to this machine and try to get a little more life out of it or recycle my current desktop into a server. It is an HP tower (m8200n) Athlon 64 X2 6000 with 3 gigs of ram. It currently runs Vista.

I have a 3-pack upgrade for Win7 so I am planning to upgrade this PC to Windows 7 no matter what I do with it. My question is, would you consider using Windows 7 as a headless server, or am I just asking for trouble? I don't want to spend $100.00 for WHS right now.

I see lots of people using Win7 as a standalone but not much talk of it as a server. Also, is there any advantage to 64-bit with SageTV?