Odd behaviour on DRAM speed

[fab68]

Hi all, i have 2x8gb g.skill tridentx 2666cl11, i4770 (non K), hero MB... if i set bclk to 104 and ddr3-2400, i go noticebly faster than ddr3-2666 (exactly same DRAM setings, XMP Profile 1).... 36.000 vs 27.000 on Aida64 memory read.... the same happens at ddr3-2400 if i just change bclk from 104 to 105... dram performance drops from 36.000 to 27.000 ... i can't sort out this strange behaviour... i'm obviously missing some important aspects.... any input appreciated thanks,

[fab68]

really no hints ? am i the only one with those kind of problems ? i could really use some help....

[clubfoot]

What happens to your DRAM Timings?

[fab68]

timings remain the same... i manually set 11-13-13-35-2t (default values), i check them with gpu-z, it reports the correct data and frequency... i made many other experiments yesterday, but there it is : at fsb 104, dram set at ddr3-2400, default xmp timings, i get 37.000 in aida 64 extreme memory read... if i just change fsb to 105, reboot, it get back to 26.000... on a side not, memtest86+ reports a memory speed when running at 105 - ddr3-2400 slights more the 104, so that appears to be right... on the other hand, when i try 104 and ddr3-2666, even memtest86+ reports a speed that is 30% less then 104@ddr3-2400, absolutly same timings....

[jab383]

I have seen that happen when I step RAM speed up. It could be that BIOS or windows can't get along with that speed without trying harder. At the bottom of the DRAM Timing tab in BIOS is a setting for Extra Training. (At least it's there on my M6F.) Try enabling that to give the system more chance to get used to the RAM speed.

Jeff