DL980 G7 QPI Speed only 4.8 GT/sec

[Stephan-Nam]

Hi,

We recently purchased an HP DL980 G7 with the following Spec:

4x Intel® Xeon® E7-2860 (2.26GHz/10-core/24MB/130W)

32x 8GB (1x8GB) Dual Rank x4 PC3-10600 (DDR3-1333) Registered CAS-9 Memory Kit - A0R56A

If working by the information available, it looks like the QPI speed of the Server should be running at 6.4 GT/s, and not 4.8 GT/s.

I also used the following link: http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c02525017&lang=en&cc=us&taskId=&prodSeriesId=4231377&prodTypeId=15351

And per memory board (total of 8 boards), we have 8A, 1A, 6B and 3B populated. Thus having 4x 8GB per memory board. As per HP's documentation, this is an optimal config.

I do not understand why the CPU steps down the QPI bus to 4.8 GT/s, do I really need to populate All 8 Banks on all 8 Boards having a Total of 512GB RAM just to "unlock" QPI of 6.4 GT/s.

Even my small DL360 G7 servers can do QPI 6.4, and my biggest server can only do QPI 4.8, even stepping down the memory speed to 800MHz.

I've tried numerous BIOS setting combinations to disable Power Capping, or Power Saving / Balacning Features. Nothing worked, and my server had to go into production on QPI 4.8 :-(

Can someone please shed some light on what we need to do, and why HP would ship a DL980 G7 with a config that only does QPI 4.8?

Regards

Stephan-Nam