I know that is not really answering your question, but I still would like to share a bit of my experience.
I have 2 E5200, both are in gigabyte G31M-S2L board, what I picked up for around $60 one is running at 3.65 the other at 3.75Ghz. Both running with the built in video chip.
Since the E5200 doesn't have the proper VT, can't run 64-bit vmware client, I am running native linux (64-bit Ubuntu) on it.
The A2 cores are available only in linux smp.
While it can run an A2 WU at ~3500 PPD, a typical A1 WU slows it down under 1700 PPD. The windows SMP would be even slower.
I know that it would not give you any comparable video editing capability, but maybe you could put the quad in your existing mobo, and reuse the E5200 with a cheap mobo as a dedicated folder. You can run the diskless notfred linux client on it off a $10 USB stick