DL585 G5 now has 3 core CPUs

[don_m]

We have a DL585 G5 with 4 x 4 core Opteron 8384 processors. Due to a software licensing issue, we needed to have this system running with only 8 cores.  Turns out there is a BIOS setting to "disable half cores".  Exactly what we need.

Changed the BIOS, rebooted the box, OS (SLES11 SP1) came up and guess what /proc/cpuinfo reported ??  6 cores. This is odd  -  16/2 = 8  not  6   And the OS saw all the RAM (fully populated on all 4 CPU banks).

So I pulled out processors 3 & 4 , the VRM modules, and the RAM from those banks. Set BIOS back to "all cores enabled". Rebooted. OS still sees 6 cores.  Now I check the ILO system information page.  It show we have 2 x 3 core CPUs under the "execution technology" line.

Called HP support, they had me update BIOS and clear the NVRAM. Made no difference. Still 2 x 3 cores.  They are presently researching this issue.

Has anyone ever seen this type of problem before ??

thanks,

Don M.

[Jan Soska]

Hello Don,

We had the same problem with HP G5 AMD servers. Possibility to disable some core came with som bios update but it didn't work properly until NVRAM was cleaned by switch on motherboard (and of course latest bios was installed). It was the same on all servers, but NVRAM always helpded.

Please make sure you clear nvram with mobo switch, if doesn't help, it is a task for HP support but it really should work.

Jan