I tried that just now with ESC, F1, ThinkVintage but still no post and only the same 4x4 beeps. Only now that i have fully reassembled it the hard drive spins.

I'm not sure that's necessary. Maybe it's enough to just remove one of the 1GB sticks. I tried all possible slots and sticks and no sticks and still the same 4x4 beeps

So i need to find a cmos/or modify one so it has a 2 pin cable, and find a 512mb ram stick. Ok, I'll try that

Hello, I have an old ThinkPad(z61m), that has worked before, that beeps 4x4 times. The main battery is dead. In the manual I found out that it is a system board(security chip) issue. The cmos battery - CR2032-BV1(LF) is also dead(0.03v), and it has 2x1gb ram configuration. How do I start...