Very Slow ECC Memory on Intel Server Motherboard

[idata]

I have a Intel S5520HCT motherboard with duel Xeon L5630 running Windows 2008 R2. I am using Kingston DDR3 1066 Parity Registered ECC memory (KVR1066D3D8R7S/4G). On the Kingston website it says this RAM is certified for my motherboard and CPUs.

However, when I install 48GB of RAM (all channels filled) the performance is so poor the system is almost unusable and the CPU utilization is near 100% when I run even the most simple program. When I remove 2 RAM modules from a channel on each CPU/memory-controller (now 32GB total) the performance vastly improves to an acceptable level.

I thought this may be a problem with the Registered memory, so I took non-registered ECC 4GB RAM (KVR1333D3E9SK2/8G) from two other machines and installed them. But shockingly I saw the same behavior. So it is obviously something with the motherboard.

Has anyone experienced this behavior before, and if so how did you solve it?

Regards,

Kevin

[Edward_Z_Intel · Accepted solution]

Try this one:

http://www.intel.com/support/motherboards/server/sb/CS-031941.htm http://www.intel.com/support/motherboards/server/sb/CS-031941.htm

[idata]

Thanks Edward. This worked!