Athcool and system crashing

I was using athcool for quite sometime. Then I changed a memory module and things started to crash. If I disabled athcool, things worked just fine.

I was spying on the memory module's SPD info, and noticed it supports self-refreshing. The old one didn't. I then tried to put another memory module aside with this, and things magically works again, even with athcool turned on (it's a must, my processor is an TB athlon xp 2600, it is really warm).

It seems like the BIOS acpi handling fails to put the module in self-refreshing mode, but thinks it has, when entering ACPI C2. In other words, the memory contents seems to get lost. The memory controller seems to correctly refreshes both modules, if at least one of then needs external refreshing.

The mainboard is an ASROCK K7VT2.