I have quite a bit of experience now with P-M's using an ASUS CT-479 adapter on a P4P800 (SE. VM and Deluxe). EIST works without problems on all of them. I've used 2 725's (1.6 GHz) and 1 735 (1.7 GHz), and all have run with a 33% overclock while undervolted using EIST.
Yes, you are right. I had the CT-479 in my mind, but it didn't seem to be a very "clean" solution. It's not on the cutting edge, but not as expensive as the native boards. And the HSF was an issue, too.
After going through this
post at xtremesystems.com last posts, I learnt that you can use a Zalman 7000/7700 and that EIST is working (on some boards). Btw, EIST is short for Enhanced Intel SpeedStep. Cpuid.com offers an utility calles EIST. We should refer to it as EIST utility in order to keep things clear.
Under the light of the working EIST, I would check wether the "old" platform by Asus offers everything I need and go with it.
The power under full load should be a good deal lower compared to an Athlon 64. Have a look at this GamePC article: http://www.gamepc.com/labs/view_content ... uso&page=3