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4790K Seems Too Hot. Help?

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New Member
Jun 29, 2014
Hey everyone, I'm brand new here but looking for some help. I just put together a new build and waited out for the 4790k. Once I got it installed I set everything up and after it had been running a while, I was in the BIOS on my board (gigabyte z87-oc force) and notice the CPU temp was registered at 76^ C. I thought that was a bit high for an idle temp so I got back into Windows and ran HWmonitor. I saw a very big difference between the BIOS temp and the temp in HWmonitor. Why would this difference be so high. The BIOS displays temp in real time, as I shut the machine down for about 30 minutes and brought it back up. Went straight to BIOS and watched the temp go from 25^ C to 76^ C in about 3 minutes. I'm using the stock fan that came with the processor to gauge performance on the fan itself. Getting an actual cooler Tuesday.

What could cause this? Also, in BIOS my CPU shows as 4400mHz but within CPU-Z it seems to bounce around quite a bit. It will show as low as 800 and as high as 4400. Is this normal?

Sorry for the newbish questions. I just want to make sure that I don't fry my brand new processor before I even OC it. Thanks for any help! :)


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My first guess is that you do not have the heat sink seated properly on the CPU.

1. Did you remove any clear plastic protective film that may have been covering the base plate of the heatsink?
2. Did you remember to use TIM (Thermal Interface Material) between the heat sink base and the CPU? This is a paste like material that fills in gaps and makes for better heat transfer between the CPU top and the heat sink base.
3. Is the cooler's fan turning?
4. What is the make and model of your case and do you have good air flow through the case? What about case fans? How many and how big are they? Which ones are set up for intake and which ones are set up for exhaust?

My biggest concern is your core voltage. It's showing 1.410 in CPU-z and I think that's considerably on the high side for that CPU at idle.

You are seeing those wide fluctuation in frequencies because of Intel's Speed Step technology and other power conserving technologies at work which take turns running the different cores at full speed but throttles back the other ones. Normal.
4.4 GHz is the max turbo boost speed. When idle or under very light use, it's common for the CPU to throttle down to what your seeing. If you'd like to see it at full speed all the time, then disable EIST and all the C-States in BIOS.

I don't see on Gigabytes website where they have released a BIOS version that officially supports the Devil's Canyon CPU on that motherboard. Why did you purchase a Z87 based board? A Z97 based board is what you should have probably purchased. It might be worth an email to Gigabyte to see if they have a BIOS that officially supports the 4790K.
ej1fr3ak, Welcome to the forum those temps do seem very high. For starters a screen shot of Hwmonitor with the Temperatures and also the Voltages expanded would be helpful.

The reason you are seeing the multiplier jumping all over the place is most likely the power saving features just reducing the clock speed to save power. It is nothing to be concerned with. What concerns me is the voltage reading in the second Cpu-Z showing 1.41 V. It is most likely the reason why your temps are so high. Did you try overclocking the chip or clicked on any overclocking features in the BIOS? I would start by doing a clear CMOS and see if that returns the voltage and temps to normal. If that doesn't help you may need update the BIOS on the motherboard to the latest BIOS if that hasn't already been done.

You should also list all the components in the Rig including what type of heatsink and how many fans are in the case, be specific as possible. Just to let you know this is a Us east cost based forum so you will need to have some patience for answers. You will probably get more help in tomorrow morning. But for now try the suggestions I said.
Yea, I saw F9 supports new 4th gen, but that was back in march when the non K CPU's were released. Not positive that covers Devil's Canyon too.
Yes, your right.... I never looked at the CPU compatibility list...LOL. I was just looking at the description of the BIOS version on the download page.
Hey guys, I'm going to try to answer all of the questions:

First, I'm not new to building systems, I first used the thermal paste that came on the heat sink with the processor. I felt like that might be an issue so I removed all the thermal paste and readded some Arctic Silver in the standard fashion of adding thermal paste when building any new system.

Next, I mentioned I am using the stock CPU fan and sink. At least until Tuesday when I get my new cooler ordered. The stock fan is spinning and showing as 2k rpm in BIOS. As for the case, here is a link to my build:


Notice storage and video card are not listed as they are already owned.

Next, I checked and double checked my bios. I reset the BIOS because I too was worried about the voltage. BIOS is at f9 and I checked to make sure that the 4790k was supported in that version and it is.

As for the detailed screenshots, See below.

Let me know if I can add anything else to help :)


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Ah and also, I went with this z87 board because it's easier to hackintosh. That was the plan but it seems a lot of other people are having issues hackintoshing with the 4790k. :(
set your cpu ratio to 44.
set your vcore to 1.25.
set your llc to the lowest setting.
Well the problem is definitely the voltage, 1.464 assuming it's a correct reading is way too high for a stock 4790k. If resetting the BIOS didn't take care of it I see two choices. Get in touch with Gigabyte and see if they have a newer BIOS or drop the voltage manually and test it. I don't know what the stock voltages are for the 4790k's but it should be around 1.2 V.
Yes I agree. This is right out of the box. I found another forum and a user there who tested the 4790k said theirs was 4.3 right out of the box, similar to this. They too had to dial down their settings to make it more like a real 4.0 processor. As for the rest, I reset BIOS to factory settings and the following are what is it set to after a reset.


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