Advice. socket 771 and pc3200/400Mhz DDR2?

Ok, work was throwing out some dead hardware and I scored a couple of Xeon 5160 CPUs
I also managed to get a heap (12G) of DDR2 ECC/reg pc3200(400Mhz) RAM

Now, I'd like to whip up a nice little server for coloing and all I need is a MB and coolers.
The problem is, all the MBs I can find on Ebay are 533/667 Mhz DDR2 RAM only.
I thought it was a chipset thing and I was screwed (only a few 771 chipsets out there and all by intel) but I was roaming about tyan's site in the memory config database and they had a couple of MB that they'd tested some 400mhz RAM on (i5100x, s5375) (intel 5100 chipset)

Now, the question is, will any 771 MB take the 400Mhz RAM and just go a bit slower?
Or should I look for any 5100 chipset board?
Or, is this a total crapshoot?

Sky