G.SKILL DDR3 2000 Ripjaws 3x2Gb + Command Rate

[wevsspot]

Memory Modules Part Number
G.Skill DDR3 2000 3x2Gb Kit CL9
F3-16000CL9T-6GBRH

Motherboard
Asus P6TD Deluxe
BIOS version 0501

CPU
Intel i7 920 D0 revision

Just a question for the experts. No matter what I try this memory will not run at 2N command rate at anything above 1600Mhz. And I have tried everything. The memory runs spectacularly at 1900 or even 2000Mhz if I set the command rate to 3N. But anything other than that and the machine fails to post.

Now, keep in mind that I'm perfectly happy with the performance at DDR3 1904Mhz and 8-8-9-24 3N timings. It is wonderful. But curiousity is killing the cat. I just can't figure out why this kit refuses to run on this motherboard with a 2N command rate.

Pertinent Information
Blck 190
CPU Multiplier 20
CPU Voltage 1.30000

Memory Divider
5:1
Timings
8-8-9-24
Frequency
1904Mhz
DRAM Voltage Control 1.64

QPI DRAM Voltage 1.45 (have tried up to 1.55)

All other memory subtimings left at Auto

Any ideas?

I've played around with RTL but havent had much success. Current RTL values as set by the BIOs are 59-60-61

tRef is auto at 98

Any thoughts or ideas would be appreciated.

Thanks.

[wevsspot]

Wow, this must have everyone stumped........

[GSKILL TECH]

Sorry, just a little backed up. Is it capable of 1N or 2N at lower frequencies?

Thank you
GSKILL TECH

[wevsspot]

1N and 2N up to 1700Mhz

After that it's 3N only. It's not a huge issue as here is my bandwidth and latency performance at current settings;


By wevsspot at 2010-08-12

cpuz incorrectly reports a 1T command rate - that is wrong