2-nd CPU (CPU1) on DL380 G3 doesn't pass Smart Start testing

[Boris Demin]

My Proliant DL380G3 with single CPU (X3.06GHz/533MHz/512kB) passes Smart Start diagnostics perfectly. But had i install second processor on the server the following error messages apear:
(in Error log) - "Unable to select/run processor: error code - 010143", and "error code - 000000".
(in IML) - "CPU stress test error, code 00000000, missing error description" and "CPU1 mmx Register Test Error Code:00000000, Missing error description".
I have checked if the CPU1 itself is OK. Yes, it works fine on another server (ML370G3) as both first and second CPU.
I reflashed the CMOS utility. Now it is the newest available on HP website. It didn't solved the problem, though. I clear the IML log but the same error message apears again.
Can you suggest me, what can cause the problem and how can i get rid of it? Please!