>> I have bought the exact same DIMMs as the guy from the Czech forum.
>> [...] Kingston KVM266X72RC25

> Unfortunatelly these DIMMs didn't work for me - my MB rev. is 2B2.

Now that's confusing. In the thread I linked to in comment #11, you reported that you had successfully running a 2B1 revision board with 2 GiB of RAM. Which DIMMs were these? And what happened to your 2B1 board?