PXD38G1866ELK Issue

[Kruasa]

PXD38G1866ELK (Viper Xtreme PC3-15000, 1866MHz, Division 2)

ASUS Sabertooth Z77

Intel i5 3570K


Under automatic settings, the motherboard sets the DRAM frequency to 1333 MHz. This seems to be consistent with what ASUS AISuite and CPU-Z thinks the RAM's maximum bandwidth is (AISuite shows 667, CPU-Z shows PC3-10700 (6677 MHz).

If I force the RAM to run at 1866 via Manual or XMP, CPU-Z shows the following:

DRAM Frequency 933.4 MHz
FSBRAM: 1:7
CL: 9.0
tRCD: 11
tRP: 9
tRAS: 27
CR: 2T

However, both AISuite and CPU-Z both still show maximum bandwidth of 667MHz (PC3-10700). Also, under Manual set to 1866 and XMP, performance is noticeably slower than Automatic at 1333 (1:5, 9-9-9-24-2T) while running the same applications, and occasionally my computer will blue screen. Using different RAM Slots seems to have no impact on the results displayed.

How can I get my memory to perform at its listed specs?

[Patriot_Ben]

Hello,

I'll be glad to clarify. CPU-Z is showing you the live correct frequency under Dram.

All Patriot Memory will be programmed to follow Jedec Standards. For most of our overclocked lines require a voltage increase to achieve the rated speeds; the memory will boot at lower speeds for compatibility across different platforms. You will need to manually set the timings in the bios (since boot-voltage cannot be set).

Thus the "bandwidth" that's being displayed is simply the reflective of the speeds it is set programmed to (under default).

This verifies that you are actually running the correct speeds:

If I force the RAM to run at 1866 via Manual or XMP, CPU-Z shows the following:

DRAM Frequency 933.4 MHz
FSBRAM: 1:7
CL: 9.0
tRCD: 11
tRP: 9
tRAS: 27
CR: 2T