cpu error in proliant dl380 g3

[Ashutosh_2]

Dear sir
On Proliant Dl380 G3 server is running with 2 cpu but single cpu is detected in redhat 8.0 linux

After adding another cpu system hang
Firmware upgradation is done for dual cpu kernal is rebuild

Pl tell me any possibilities

[Vitaly Karasik_1]

1) may be just hardware problem with second CPU?

2) with smp kernel you should see 2 logical CPU even with one physical CPU because [AFAIK] all dl380g3 come with CPU with hyperthreading. So - do you see two CPU in "top", for example?