Hmm I'm not sure if you're serious about building a new PC out of that because I can't find a place around here that sells Socket A mobos anymore, but if it's for like a secondary system it'll suffice, and if you're willing to do some searching around
Back in the day I used an ASUS A7N8X-E Deluxe (nForce2 Ultra/400 chipset), and it was a very nice and stable mobo, though expensive. If you were looking for something cheaper I'd definitely look to the ASUS A7N8X-X, which is essentially a stripped-down version of the original. Though you would also have to live without dual-channel memory support.