Core speed occasionally dropping from 4.7 Ghz to 3.4 Ghz when running prime95

[spartanw80]

This has always been an issue for me on this build. Whenever I run prime95 or some other cpu benchmarking tool, the core speed and vcore will drop every 10-15 seconds and stay like that for a good 2-3 seconds. So I'm basically watching it bounce around between the frequency it should be (4.7 Ghz) and 3.4 Ghz.

Usually at 4.7 Ghz @ 1.296V
Drops to 3.4 Ghz @ 1.016V

The highest core temp I've gotten is 75 °C and it's a 3570k so I don't think it's thermal throttling.

Mobo: Asrock Z77 Pro4
CPU: i5 3570k
Cooling: Noctua NHD-14 + relidded cpu with Phobya HEGrease

It's also a 730W PSU so I don't think that it's having trouble drawing enough power.

I also have Cool 'N Quiet disabled.

 

[geofelt]

I think the tdp of the 3570K is in the range of 75c.

It sounds to me like thermal throttling.

 

[Shneiky]

Drop the OC to 4.5 GHz and lower V till stable. Test again. You should arrive at the upper 60C or lowest 70s. I think that will do the trick. Good luck.

 

[spartanw80]

I think the tdp of the 3570K is in the range of 75c.

It sounds to me like thermal throttling.

Correct me if I'm wrong, but TDP is a measurement of power and is used for the designing of cooling solutions, not a throttle temperature.

Also, I believe the throttle temperature for Ivy Bridge is 98 °C.

http://www.overclock.net/t/1198504/complete-overclocking-guide-sandy-bridge-ivy-bridge-asrock-edition

 

[Buzz247]

Thermal Design Power - The design of the architecture and what temps it can operate within and max out at. These specs are a good indication of how to design cooling and OC limits

Ivy bridge can begin throttles at 90c, shutdown at 120c max. Sub 80c is preferred load test operating temp. Daily use sub70c

1) VRM getting hot and throttling voltage (Folks forget these heatsinks need cooling to, especially when OCing
2) Power saving settings not disabled - go back to guide and double check settings
3) LLC or vdroop causing issues - go back to guide and check settings

These are the most common causes of your issue check these and let us know where things sit

 

[spartanw80]

Drop the OC to 4.5 GHz and lower V till stable. Test again. You should arrive at the upper 60C or lowest 70s. I think that will do the trick. Good luck.

This happens at 4.6 Ghz at 60 °C too.

Thermal Design Power - The design of the architecture and what temps it can operate within and max out at. These specs are a good indication of how to design cooling and OC limits

Ivy bridge can begin throttles at 90c, shutdown at 120c max. Sub 80c is preferred load test operating temp. Daily use sub70c

1) VRM getting hot and throttling voltage (Folks forget these heatsinks need cooling to, especially when OCing
2) Power saving settings not disabled - go back to guide and double check settings
3) LLC or vdroop causing issues - go back to guide and check settings

These are the most common causes of your issue check these and let us know where things sit

I'll go double check my power saving settings and mess with vdroop. I have vdroop set to 50% right now. As far as VRM temps go, I'm not sure if HWMonitor is seeing those are not. While under the Intel Burn In Test my mobo temps were as follows:

SYSTIN: 32 °C
CPUTIN: 45 °C
AUXTIN: 43 °C
TMPIN3: 91 °C

 

[Buzz247]

TMP0/1 sensor is your socket sensor. That should be lower than CPU reading. in your case if it far higher - and oddity to say the least. Shutdown HWMon and try Real Temp program. See what read you get. It is POSSIBLE that on your board the TMP is your VRM sensor, which would make sense for what you are experiencing

at 4.6, what are your bios voltages all set at?

edit TMP3 is likely a northbridge sensor on that program reading. lil high but not enough to cause crashing of voltage

 

[spartanw80]

TMP0/1 sensor is your socket sensor. That should be lower than CPU reading. in your case if it far higher - and oddity to say the least. Shutdown HWMon and try Real Temp program. See what read you get. It is POSSIBLE that on your board the TMP is your VRM sensor, which would make sense for what you are experiencing

at 4.6, what are your bios voltages all set at?

edit TMP3 is likely a northbridge sensor on that program reading. lil high but not enough to cause crashing of voltage

At 4.6V it's a +0.102V offset which, with 50% load line calibration, gives me 1.232V

I'll also try real temp instead.

I also don't seem to have this issue when running Intel Burn In Test. The issue might have actually been with prime95.(nvm, it's not happening with prime95 at 4.6 anymore either) Anyways, my max core temps using RealTemp were 64,69,71,67

 

[Buzz247]

Excellent guide and made with AsRock Bios settings in use - works for all Ivy bridge:

http://www.overclock.net/t/1198504/complete-overclocking-guide-sandy-bridge-ivy-bridge-asrock-edition

check against these settings suggestions

 

[spartanw80]

Excellent guide and made with AsRock Bios settings in use - works for all Ivy bridge:

http://www.overclock.net/t/1198504/complete-overclocking-guide-sandy-bridge-ivy-bridge-asrock-edition

check against these settings suggestions

I actually referenced that guide a few comments up

 

[Buzz247]

lmao so u did!!! oops my bad