I solved the issue
SOLVED!
Okay, so the thing is - you have to screw the heatsinks well enough. But be careful, and do it in turns. So the last time, when i got to the point that computer turns on and stops (no video, no chime) but no longer puts out any warning leds, it means you have to screw the heatsink to the processor a little more. Start with just processor A, and slowly but surely, add more turns as does this guy in the video here :
https://www.youtube.com/watch?v=YAdgT-hJuXU
I had the same exact symptoms - at first, when the cpu is not fastened enough, you can get a pulsing power light and possibly fans loud on, then you make another half turn-full turn (be careful) and you get past that, the next symptom may be that the cpu board does not recognize all the memory, you have to screw some more, remember that slots 1-4 belong to CPU A, 5-8 to CPU B, so if your board does not recognize slot 5, that means CPU B needs a little more love
![Smile :) :)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
be careful ! slowly and surely, thats the clue
another thing - I was told by the seller from ebay that SMC version on cpu board does not matter, it should boot anyhow. That was the impulse i needed. I started with CPU A, and went thru the steps that i written about above. Then had a lot of reserve ( I was cautious) about screwing the CPU B harder, but looks like it needed a little more than CPU A, go figure. I tried it four times with different CPUS (i thought that maybe they were broken) and after giving it a bit more turns finally the board saw both cpu's.
After i booted into os x, i saw that my smc version for the logic board (that i updated to 5,1) was the same (1.39f5) as the smc that came with my new cpu board 2009 from the shop - 1.39f5, too. my boot rom is MP51.007F.B03. Looks like i have a spare double cpu board now with 2 cpus
A lot of screwing, i know
but maybe it will help somebody, i know i needed help badly a week ago. Learned a lot. ask any questions if something is not clear.
Cheers!
B