Was just reading an article from AnandTech about a computer show in Hong kong. Here's what they say about Athlon 4 and motherboard issues.
"AMD unveiled their new Athlon core with the Athlon 4 a couple weeks ago. While no benchmarks have been published yet, the question remains whether the new processor will work on current motherboards. We took this chance to ask ABIT if they have any information on this topic with respect to their popular KT7A-RAID. He told us that, so far, their testing has been quite positive and that the Athlon 4 chips they have in hand are working properly on the KT7A-RAID.
When asked if this is because the KT7A-RAID has a very wide range of CPU core voltages (from 1.100 – 1.850 in 0.025V increments), we got a somewhat surprising response. While voltage values available on the board could be an issue, the most important piece of the puzzle is the necessary circuitry for detecting the chip correctly. They said that the circuitry on their current KT7A-RAID is already capable of detecting the Palomino core and that's the main reason why the chip will work on their board, but possibly not on others.
This is quite surprising since we previously thought that voltage would be the most important factor for getting the Palomino to work on a KT133A. However, if the correct circuitry is really what is needed for this to happen, it could be bad news for those KT133A users whose boards happen to not have this circuitry since no BIOS update can fix that. We have yet to see how other manufacturers will address this issue, though, and we'll be doing our own testing in the lab soon enough".