ASRock Z77 Extreme6 + 2 x F2-14900CL9D-8GBXL Kits (4 sticks) settings

[Zxaos]

Hi all,

I'm looking for some advice about ram timings for my new build.

I'm running
Motherboard: ASRock Z77 Extreme6
Memory: 2 x G.Skill F2-14900CL9D-8GBXL kits (4 sticks, 16GB total)
CPU: Intel i7-3770k

The system is running BIOS version 1.90 and is not overclocked in any way.

The ram timings are as suggested, 9-10-9-28.

The system is stable when running only two sticks, but when I run with four sticks, I get memtest errors. I've tried incrementally upping the voltage but even with the DRAM Voltage set as high as 1.65 I'm seeing problems with memtest (granted, there are fewer problems at 1.65 than at 1.5).

I'm not sure what my next steps should be here. Is it just not possible to run the ram at the listed timing with four sticks?

[Tradesman]

Yes it's possible, but with two sets, XMP won't work and set the correct advanced timings, they have to be done manually, the biggest problem is probably the tRFC, may want to try it around 170, if no joy, can you post your timings (base and advanced) and system voltages

[Zxaos]

So I tried that suggestion last night - got 9 errors in 9 hours with memtest. Here's the settings I used:

DRAM Frequency: DDR3-1866
DRAM Voltage: 1.600V
tCL: 9
tRCD: 10
tRP: 9
tRAS: 28
CR: 2N
tWR: Auto (14)
tRFC: 170
tRRD: Auto (5)
tWTR: Auto (8)
tRTP: Auto (8)
tFAW: Auto (24)
tCWL: Auto (7)
ODT WR (CHA, CHB): Auto
ODT NOM (CHA, CHB): Auto
MRC Fast Boot: Enabled

I can post CPU settings as well, but pretty much everything is just running with Auto settings at this point.

Any suggestions about further adjustments?

[Tradesman]

tWR 16 tRRD 7 tCWL 8 tFAW 25, and may want to raise CPUVTT to 1.1 or so

[Zxaos]

No luck with those settings either, still getting memtest errors.

(CPUVTT was slightly higher than 1.1, but was at the first step available higher than 1.1)

[Tradesman]

How do the sets work individually, i.e. can both sets work by themselves under XMP or manual, or does one work and not the other? Can test each stick individually with Memtest (4-5 passes) should tell if each stick is good or if there's a bad one. May just have two sets that dont want to play together, especially with this mobos BIOS

[Zxaos]

I've tested both pairs individually at 1866 9-10-9-28 1.5V (from the XMP profile) and they both pass memtest successfully (multiple passes).

I haven't tested each stick individually because both pairs passed, but I can test individually if you think it would help?

[Tradesman]

Might try 1.65 DRAM Voltage

[Zxaos]

Bumped the DRAM Voltage to 1.65, and the CPUVTT to slightly less then 0.5V lower, and still no luck.

Seems you might be right about having two sets that don't want to play nice together.

[Tradesman]

It happens, generally slight voltage adjustments will make the sets be nice to each others, but not always, theat was one thing sort of nice with DDR and DDR2, the tolerances weren't so tight and it was generally each to just mix most any sticks

[Zxaos]

Well, thanks for trying!

Do you think there would be any point in trying to return my two pair kits and going and picking up a F3-14900CL9Q-16GBZL (4Gx4) kit instead? Is that likely to work, given the issues I've experienced?

[Tradesman]

I'd give it a try, with two sets it can be problematic, possible you just got 2 that wouldn't play together, which does happen on occasion