- Feb 3, 2012
- 21
- 0
- 18,510
Hi everyone, I already started a thread about my problem a few days ago when it started, but I didn't know much about the cause then and thought the title was not describing it well enough, so I created a new thread. Anyway, I'll try to keep this as short as possible; thanks in advance to anyone who reads this and tries to help.
Basically, I can't seem to find a stable setting for my 1.65V OCZ Gold RAM at 1600 MHz using my "new" i7 980X. I switched this CPU two days ago with my 930, which was giving me no problems after finding the correct settings through experimenting and testing. I'm not even trying to overclock the CPU here, just trying to get the RAM to pass memtest at its rated speed while using stock speeds for the CPU.
My stable configuration for the RAM with the 930 was:
BCLK: 133
Uncore multiplier: 24
Memory multiplier: 12
QPI / uncore voltage: 1.300 V
DIMM Voltage: 1.62 V
Command Rate: 2T
DIMM Reference Voltage Training: OFF
From what I've read, the only difference between the 980X and 930 concerning RAM is that the 980X is able to accept a minimum Uncore multiplier / memory multiplier ratio of 1.5 instead of the 2.0 for the 930; which means I should be able to go below 24. And that does happen, however strangely enough, I can't go above 21. When I do, POST fails even if I take QPI / uncore voltage all the way up to 1.375 V.
Now I've got to say first of all that I'm reluctant to change any of the settings that concerns only the RAM and nothing else (such as timings and DIMM voltage), because I had these settings work fine with the 930, and since (from my understanding) these settings have no dependency on the CPU. Although I've tried a few combinations with DIMM voltage set to 1.66 V and DIMM Reference Voltage Training and Command Rate set to auto just in case. It felt less stable with Vdimm at 1.66 V. The other two didn't seem to make a difference.
I'm guessing the problem is about finding the correct Uncore multiplier and QPI / uncore voltage combination. I've tried so many combinations but still couldn't get a clean memtest result. It seems that an uncore multiplier of 18 and QPI voltage of 1.250 is most stable (however, still unstable overall) as it can always complete a single pass on memtest until it starts giving errors. There are a few more combinations that also do this. As far as I can remember uncore 20 & Vqpi 1.250 was also similar, but the PC feels faster with uncore 18 (or it might just be me). Has anyone got experience with overclocking the 980X or 990X?
Also:
1) Does the time it takes for memtest to produce errors correlate to the level of stability? (I know stable should have no errors, but at least the tests should tell you whether you're getting closer to or further away from the sweet spot, right?)
2) Should I also be looking at changing Core voltage even though I'm not overclocking the CPU? Could this have an effect on stability at stock speeds?
3) Should I have the dynamic power options such as Speed Step disabled or enabled?
4) Can things like Turbo Boost or HT have an effect on this, ie. if I disable them could it help?
5) What about some of the other settings like IOH core voltage or CPU VR Current or Power Override settings?
6) Can I trust memtest? Should I double check each unstable configuration using memtest86+?
Basically, I can't seem to find a stable setting for my 1.65V OCZ Gold RAM at 1600 MHz using my "new" i7 980X. I switched this CPU two days ago with my 930, which was giving me no problems after finding the correct settings through experimenting and testing. I'm not even trying to overclock the CPU here, just trying to get the RAM to pass memtest at its rated speed while using stock speeds for the CPU.
My stable configuration for the RAM with the 930 was:
BCLK: 133
Uncore multiplier: 24
Memory multiplier: 12
QPI / uncore voltage: 1.300 V
DIMM Voltage: 1.62 V
Command Rate: 2T
DIMM Reference Voltage Training: OFF
From what I've read, the only difference between the 980X and 930 concerning RAM is that the 980X is able to accept a minimum Uncore multiplier / memory multiplier ratio of 1.5 instead of the 2.0 for the 930; which means I should be able to go below 24. And that does happen, however strangely enough, I can't go above 21. When I do, POST fails even if I take QPI / uncore voltage all the way up to 1.375 V.
Now I've got to say first of all that I'm reluctant to change any of the settings that concerns only the RAM and nothing else (such as timings and DIMM voltage), because I had these settings work fine with the 930, and since (from my understanding) these settings have no dependency on the CPU. Although I've tried a few combinations with DIMM voltage set to 1.66 V and DIMM Reference Voltage Training and Command Rate set to auto just in case. It felt less stable with Vdimm at 1.66 V. The other two didn't seem to make a difference.
I'm guessing the problem is about finding the correct Uncore multiplier and QPI / uncore voltage combination. I've tried so many combinations but still couldn't get a clean memtest result. It seems that an uncore multiplier of 18 and QPI voltage of 1.250 is most stable (however, still unstable overall) as it can always complete a single pass on memtest until it starts giving errors. There are a few more combinations that also do this. As far as I can remember uncore 20 & Vqpi 1.250 was also similar, but the PC feels faster with uncore 18 (or it might just be me). Has anyone got experience with overclocking the 980X or 990X?
Also:
1) Does the time it takes for memtest to produce errors correlate to the level of stability? (I know stable should have no errors, but at least the tests should tell you whether you're getting closer to or further away from the sweet spot, right?)
2) Should I also be looking at changing Core voltage even though I'm not overclocking the CPU? Could this have an effect on stability at stock speeds?
3) Should I have the dynamic power options such as Speed Step disabled or enabled?
4) Can things like Turbo Boost or HT have an effect on this, ie. if I disable them could it help?
5) What about some of the other settings like IOH core voltage or CPU VR Current or Power Override settings?
6) Can I trust memtest? Should I double check each unstable configuration using memtest86+?
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