Maximum CPU power and temperature

[Denna]

Using a 4790K on a Maximus VI Gene with Intel Speedstep enabled and Windows 8.1 64-bit.

When CPU speed is pushed to maximum for less than 45 minutes, at what point should the CPU wattage, CPU voltage parameters and CPU temperature dictate the maximum safe overclock ?

I'm testing to determine the safest maximum CPU speed for programs demanding it intermittently, but not for 24/7 usage.

[Nate152]

Hello Denna

What dictates the maximum safe overclock is your cpu temperatures. The Nepton 140XL should be able to handle 1.30v - 1.35v.

Start with 1.30v and set the cpu core ratio to 47 and run the realbench 15 minute stress test. If you pass the test try the core ratio at 48.

http://rog.asus.com/rog-pro/realbench-v2-leaderboard/

Temps may hit 90c when running the stress test and that's ok. Then see where temps are while playing a game or running your other programs, 75c or below is what you want to see.

If you don't have a cpu temp monitoring program you can use real temp 3.70.

http://www.softpedia.com/get/System/System-Info/Real-Temp.shtml

ROG cpu-z for cpu voltage monitoring. Select cpu-z 1.73 then scroll down and select ROG version.

http://www.cpuid.com/softwares/cpu-z.html#version-history

[Janne-71]

Nate152 wrote:
Hello Denna

What dictates the maximum safe overclock is your cpu temperatures. The Nepton 140XL should be able to handle 1.30v - 1.35v.

Start with 1.30v and set the cpu core ratio to 47 and run the realbench 15 minute stress test. If you pass the test try the core ratio at 48.

http://rog.asus.com/rog-pro/realbench-v2-leaderboard/

Temps may hit 90c when running the stress test and that's ok. Then see where temps are while playing a game or running your other programs, 75c or below is what you want to see.

If you don't have a cpu temp monitoring program you can use real temp 3.70.

http://www.softpedia.com/get/System/System-Info/Real-Temp.shtml

ROG cpu-z for cpu voltage monitoring. Select cpu-z 1.73 then scroll down and select ROG version.

http://www.cpuid.com/softwares/cpu-z.html#version-history

I suppose that applies for skylake 6600k also? That temps during rog realbench stress test can be over 80c and its acceptable.

[Denna]

Nate152,

Thanks for the detailed response.

As I mentioned to Arne in my thread "CPU Strap usage" a few minutes ago, I haven't been using Realbench since the download size is greater than the amount of data usage left on my limited data plan. I'll have to wait until Sept. 2 to download it when the billing period restarts.

So far I've been using one instance of a Powershell script to push the processor to the maximum speed (5.04 GHz) and monitoring the voltages and temperature in AI Suite III. Below is the script. At 5045 MHz, it's running for 41m44s and usually produces 16-17% CPU utilization per instance.

Measure-Command {$result = 1; foreach ($number in 1..2147483647) {$result = $result * $number}}

When you say the Nepton 140XL should be able to handle up to 1.35v, does that mean you're correlating temperatures most people associate with 1.35v ?

Right now, AI Suite III is displaying ~45C at 5045 MHz with a CPU Core Voltage of 1.456v. CPU-Z is showing a Core Voltage of 1.456v with a Core Speed of 5139 MHz.

Does that mean the CPU Core Voltage should not be set greater than 1.35v when using a Nepton 140XL ?

The end result, hopefully, will be:

• A ~5 GHz max speed that will drop to ~800 MHz when not needed. MahJong games don't demand a high sustained CPU load, but Batman: Arkhan Knight sure does.
  
• Voltages that drop under low load.
  

What I'm doing now is more of an exploration to see what this system can do for short term bursts under heavy load.

[Denna]

Nate152,

Here's a couple screenshots from Real Temp.

The first screenshot was taken while the script was running. The second screenshot was taken after XS Bench was run.

It's curious how one core would always be in the 30's, two would be in the 40's and one would be in the 60-70's.

What would be a good setting for Load Line Calibration for everyday use and intermittent, short duration (<10 minutes) max CPU speed ?

[Piers]

I aim to stay below 75 for every day use (encoding 1080p using x264 takes my CPU to 100% use at ~68 degrees). IntelBurnTest (a tool I've used for many years) pushed that temperature up to 85-90, which is what I expect.

[Nate152]

That's an awesome overclock on the 4790k at 5.2GHz, what voltage did you need for 5.2GHz? Your temps look great with the Nepton 140XL.

Very nice job Denna that's the highest I've seen a 4790k overclocked with an AIO cpu cooler.

[Denna]

Nate152 wrote:
That's an awesome overclock on the 4790k at 5.2GHz, what voltage did you need for 5.2GHz? Your temps look great with the Nepton 140XL.

Very nice job Denna that's the highest I've seen a 4790k overclocked with an AIO cpu cooler.

Nate152,

I apologize for not noticing your reply. Subscription e-mail alerts seem to be hit or miss.

RealTemp reported the speed at 5,200 MHz, but that's probably not what it actually was. It was probably around 5150 or 5175 MHz.

I don't remember what the voltage was, but I'd guess it was around 1.45v using Adaptive Voltage.

However, that was a booting configuration with no software testing stability.

Right now, it's running 4,949 MHz and passing RealBench's stress tests.

Unfortunately, I can't say the Core speed starts with a "5" anymore. :mad: