I'm using an HP motherboard with Windows XP; I have PCI\VEN_8086&DEV_2772&SUBSYS_2450103C&REV_0213&2411E6FE&0&10. I'm missing a driver for the VGA Graphics Controller. Where can I find it?
Have you tried letting Windows Update search to see if it has a driver for it?
My first point of call other than that (and even if WU does find one, there might be a more up-to-date but perhaps not signed one here) HP's support/drivers area is usually pretty complete and useful whenever I've needed to get something for one of the machines here. The UK one is http://welcome.hp.com/country/uk/en/support.html - you'll be directed to the right one for your country if you go to hp.com and click "support & drivers" in the top right. You'll need a part/model number to search for. If the motherboard is in an HP machine (or was taken out of one) search for the machine's model name/number rather than anything you find written on the board.
VEN_8086 Indicates Intel as the vendor .
DEV_2772 Indicates 945G as the chipset.
Grab the driver from Intel's page --> http://downloadcenter.intel.com/Detail_Desc.aspx?agr=Y&DwnldID=16836&ProdId=2102&lang=eng
Or, grab it from HP's site as David mentioned.