Chaintech VNF4 Ultra - what's going on here?

[xbdestroya]

Ok cutting to the chase, Chaintech VNF4 Ultra in my brothers computer, X2 3800, FSB shifted to 240 at stock, CPU runs great, but the memory seems unstable. So, try changing the memory divider, upping the memory voltage, etc... but system won't boot. What's the deal here? One would assume when the system boots at a memory speed of 240 MHz, going lower would guarantee a boot, but for some reason no.

Any theories? Right now I guess I'm going to have to reduce the overclock to ensure system stability, pending some sort of logical resolution with the RAM.