Weird OC problem with 6700k and asus z170-a

[Ipso]

Hi,

I'm rather new to OCing but I think I have the basics down and succeeded at a modest OC, but then it started acting strange, which is why I'm asking if someone might know what's going on and what can be done.

First a sidenote, the first mobo I got acted up (dimm slot 1 stopped working after a week) so I returned it and have a new one now. I tried swapping dims in different slots in the old one and the dimms seemed to work, it was whenever slot 1 was populated it refused to boot with dim-warning-light lit. So I don't think that matters but thought I'd mention it in case.

The rig:

CPU: Intel I7 6700k
Cooling: Kraken x60 with fans swapped for Noctua NF-A14 PWM
Mobo: Asus Z170-A (Aisuite 3 and BIOS updated to latest version from their site, aisuite from late august, bios v 1003)
Mem: Corsair Vengeance LPX DDR4-3000 QC 32GB
PSU: Corsair AX760 760W
Graphics: GB AMD 280X 3GB

Let me know if you need any other info!

So what happened...

I aimed for 4.6 ghz with seemed what most can achieve at least, and it was pretty easy, I don't quite understand the adaptive/offset mode parameters, so I went for manual mode with 4.6GHz@1.35V and XMP for the RAM. With was fine at least for 20 min of Prime 95 torture, and a few hours of surf/gaming etc for about a week. (Those settings worked at the first mobo as well).

Then suddenly yesterday while I left it idling in win 10 for a couple of hours, when I returned, it hanged, and when booting the problems started: Almost any OC seems to not work mostly at boot, but if boot works, it mostly works afterwards. I now run at stock CPU and JEDEC 2100mhz for ram just to get it somewhat stable, and even so it got a weird bs after an hour or so yesterday.

So what I've tried
- After trying some minor changes and failing, I updated the BIOS successfully - no change, still oc problems
- Once, somehow, I got 4.6 working@1.39v (I've tried up to 1.42), it passed some prime95 and an hour surf/game, but then failed at boot next time and didn't work again!
- Tried loading default bios parameters and starting over, nothing new
- Temps are fine, 30c when idling (liquid temps seems to be 30 for some reason so the cpu wont go below that) and below 80-85c when running the "hard parts" of prime 95 torture, and 50-75c for "easier" parts, otherwise perhaps 50 during gaming (in games that use the cpu somewhat, less otherwise)
- Also trired to OC the RAM and leave the CPU but I only got that back once at XMP 3ghz (again for at least a few stable minutes and some testing), with a slightly increased ddr voltage (1.36 vs the xmp 1.35), but after that never again, raising it ti 1.38 doesnt help, tried loweing frequency to 2800 and 2600...no good.

I haven't tried say CPU 4.4ghz, but when it pulled of 4.6@1.35v for about a week...what's wrong now?

Running everything on "auto" in bios now, 4ghz with 4.2 turbo, and I may be mistaken, but it's now running at 1.4v and 1.45 at prime torture, and I think it was lower before...

I read in a few threads here about some problem with some Asus motherboards having some problem with lowering voltages after sleep, but I trired disabling c-states, and for some that was fixed in with bios, and that the z170-a hadn't gotten the fix yet, but that was 15 sept, and I think the current bios is newer (the fix may not be included of course, no mention of it on the description.)

But the weird thing is that is so inconsistent and worked a week, then acted up, but worked at oc settings a one or two times, then wont boot next time? Testing settings back and forth, suddenly it worked again using 4.4ghz@1.4v, then i tried 4.6@1.4, also ok (when I say worked I mean boot and about 10 min of prime 95 torture...usually it stops working before that if there's a problem..)! Then reboot to change to lower voltage in bios, and it doesn't even boot using the same parameters?! Back to 4.4, doesn't boot again!? I'm really at a loss here...memory at low speed all the time...

In fact, it seldom stops working during the 20 min prime 95-tests, mostly it doesn't even boot, and rarely bluescreen, but a few times now, a setting that passed a 10 min torture and some surfing wont even boot on next reboot...what's up with that, is the reboot test that thorough or is there a problem in the bios settings for booting somehow?

Now I finally managed to get the memory working at almost xmp, but lowering frequency from 3 to 2.933 and increasing voltage 0.01v to 1.36 (tried it before as well but didn't work then..)...but still stock auto cpu 4-4.2ghz@1.4-1.45v...

Any ideas?

[Keller1234]

Try flashing BIOS v0901, people have been reporting issues with the latest BIOS

[Ipso]

Keller1234 wrote:
Try flashing BIOS v0901, people have been reporting issues with the latest BIOS

Thanks for the tip, but I was on that version when the problems started...perhaps the 5-way can give be a better result on that one, but I don't think that was the cause of the problem? Or perhaps stay at the oc mentioned above, and wait for a new bios that hopefully fixes the reported problems?

I guess since it was at 50-60 during normal "heavy" use before, 60-70c could be tolerated now, but what about the voltage 24/7 at 1.47? Prime 95 torture would probably bring this to 90c...

[brkkab123]

Try running the 5 Step Optimization in AI Suite 3 and see what overclock it gives you. It also runs a stress test on your pc.

Ipso wrote:
Hi,
I'm rather new to OCing but I think I have the basics down and succeeded at a modest OC, but then it started acting strange, which is why I'm asking if someone might know what's going on and what can be done.

First a sidenote, the first mobo I got acted up (dimm slot 1 stopped working after a week) so I returned it and have a new one now. I tried swapping dims in different slots in the old one and the dimms seemed to work, it was whenever slot 1 was populated it refused to boot with dim-warning-light lit. So I don't think that matters but thought I'd mention it in case.

The rig:

CPU: Intel I7 6700k
Cooling: Kraken x60 with fans swapped for Noctua NF-A14 PWM
Mobo: Asus Z170-A (Aisuite 3 and BIOS updated to latest version from their site, aisuite from late august, bios v 1003)
Mem: Corsair Vengeance LPX DDR4-3000 QC 32GB
PSU: Corsair AX760 760W
Graphics: GB AMD 280X 3GB

Let me know if you need any other info!

So what happened...

I aimed for 4.6 ghz with seemed what most can achieve at least, and it was pretty easy, I don't quite understand the adaptive/offset mode parameters, so I went for manual mode with 4.6GHz@1.35V and XMP for the RAM. With was fine at least for 20 min of Prime 95 torture, and a few hours of surf/gaming etc for about a week. (Those settings worked at the first mobo as well).

Then suddenly yesterday while I left it idling in win 10 for a couple of hours, when I returned, it hanged, and when booting the problems started: Almost any OC seems to not work mostly at boot, but if boot works, it mostly works afterwards. I now run at stock CPU and JEDEC 2100mhz for ram just to get it somewhat stable, and even so it got a weird bs after an hour or so yesterday.

So what I've tried
- After trying some minor changes and failing, I updated the BIOS successfully - no change, still oc problems
- Once, somehow, I got 4.6 working@1.39v (I've tried up to 1.42), it passed some prime95 and an hour surf/game, but then failed at boot next time and didn't work again!
- Tried loading default bios parameters and starting over, nothing new
- Temps are fine, 30c when idling (liquid temps seems to be 30 for some reason so the cpu wont go below that) and below 80-85c when running the "hard parts" of prime 95 torture, and 50-75c for "easier" parts, otherwise perhaps 50 during gaming (in games that use the cpu somewhat, less otherwise)
- Also trired to OC the RAM and leave the CPU but I only got that back once at XMP 3ghz (again for at least a few stable minutes and some testing), with a slightly increased ddr voltage (1.36 vs the xmp 1.35), but after that never again, raising it ti 1.38 doesnt help, tried loweing frequency to 2800 and 2600...no good.

I haven't tried say CPU 4.4ghz, but when it pulled of 4.6@1.35v for about a week...what's wrong now?

Running everything on "auto" in bios now, 4ghz with 4.2 turbo, and I may be mistaken, but it's now running at 1.4v and 1.45 at prime torture, and I think it was lower before...

I read in a few threads here about some problem with some Asus motherboards having some problem with lowering voltages after sleep, but I trired disabling c-states, and for some that was fixed in with bios, and that the z170-a hadn't gotten the fix yet, but that was 15 sept, and I think the current bios is newer (the fix may not be included of course, no mention of it on the description.)

But the weird thing is that is so inconsistent and worked a week, then acted up, but worked at oc settings a one or two times, then wont boot next time? Testing settings back and forth, suddenly it worked again using 4.4ghz@1.4v, then i tried 4.6@1.4, also ok (when I say worked I mean boot and about 10 min of prime 95 torture...usually it stops working before that if there's a problem..)! Then reboot to change to lower voltage in bios, and it doesn't even boot using the same parameters?! Back to 4.4, doesn't boot again!? I'm really at a loss here...memory at low speed all the time...

In fact, it seldom stops working during the 20 min prime 95-tests, mostly it doesn't even boot, and rarely bluescreen, but a few times now, a setting that passed a 10 min torture and some surfing wont even boot on next reboot...what's up with that, is the reboot test that thorough or is there a problem in the bios settings for booting somehow?

Now I finally managed to get the memory working at almost xmp, but lowering frequency from 3 to 2.933 and increasing voltage 0.01v to 1.36 (tried it before as well but didn't work then..)...but still stock auto cpu 4-4.2ghz@1.4-1.45v...

Any ideas?

[Ipso]

brkkab123 wrote:
Try running the 5 Step Optimization in AI Suite 3 and see what overclock it gives you. It also runs a stress test on your pc.

Ok, so I tried the 5-way again, the first time a few days ago it just couldn't boot after the first reboot (even before the tests start?), so I manually changed back settings in bios and when windows started it was gone.

The second time just now, I selected TPU-I fast optimization first, with max temp of 75 and target 4600 and no preference for voltage. One reboot and it landed at 4,2 ghz only.

Tried again with TPU-II and 85c as temp limit and no voltage preference. First reboot got stuck in a bootloop with windows bs:ing with some kernel error. Manually changed to stock and disabled c-states again in bios (don't know if the optimization resets that kind of thing when done). When entering windows after that the process started. 2 succssfull boots later in the opt-process it landed on 4.4ghz for 2 cores and 4.5 for 2 cores. Core voltage seems to stay at 1.46-47 at idle and I'm not sure I like that. It seemed to stay at 1.37v during the optimization test, and never above 70c or so.

Very quick p95 torture now seems to bring it to 10c higher than my first nice oc that worked for a week flawlessly.

...so what conclusions can be drawn...have i "lost" OC potential in the CPU somehow? What could be the reason/problem?

[spanishflyer]

Can you "back-walk " to Windows 7 64 bits? I just get the feeling windows 10 is still not up to it.... (I've heard similar complaints in several forums)
BR,
Spanish Flyer

[Ipso]

spanishflyer wrote:
Can you "back-walk " to Windows 7 64 bits? I just get the feeling windows 10 is still not up to it.... (I've heard similar complaints in several forums)
BR,
Spanish Flyer

Maybe that is a reason for some of the bluescreens...but the erratic bios-post-test that fails sometimes and sometimes not on the same settings?!...Also, it's a new computer so it wasn't a win7 before (but maybe it's possible to downgrade anyway), but I don't think that solution is very appealing unless proven that win 10 is the problem, but thanks for the tip!

[Ipso]

The strange behavior continues...after yesterdays 5-way-auto OC, it was stable for a few hours today, but then bluescreen, and again, so perhaps not. I LOWERED the OC from 4.5/4.5/4.4/4.4 to 4.4 for all cores and also lowered the bclk with 1.5mhz to 100, and then the boot failed! Then I just changed from "locked" to "per-core" OC, with all other settings, clocks etc the same, and it worked!...for a few hours, but then BS in win again...

So I'm starting to wonder if some of the win BS are a different problem from the OC problems...the windows error is mostly "UNEXPECTED_KERNEL_MODE_TRAP" but not always...is that a common OC BS?

At least the memory has been working across a number of different OCs almost at it's xmp profile (2.933 instead of 3)...

[x-rated]

did you try prime95 or avx2 y-cruncher when everything set o default / after bios reflashing and nothing related to oc changed?

[Ipso]

x-rated wrote:
did you try prime95 or avx2 y-cruncher when everything set o default / after bios reflashing and nothing related to oc changed?

Hi, not really, will do, but I doubt it will be a problem, in fact, only once I've seen a problem in prime 95, mostly it wont boot, or bs before or shortly after logging on to windows...if it comes as far as p95 it usually works...until the times I've thought I was stable and then a few days or hour later a bs and then back to the problems were almost nothing is stable again no matter settings...(surfing at the bios-overclock-failed 1800mhz cpu/ 2133 mem...) until a while later it is possible to oc again...

But that has made me wonder if the bluescreens are really an oc problem...perhaps there's something else as well..