Hi all,
Since yesterday I have a new CPU (RMA). I've done some (short) tests with Prime95 small FFT's and I can confirm that based on these tests, the max temperature seems to be 10°C - 15°C lower. Without any BIOS adjustments I'm getting temperatures beginning 80°C. I have to admit that besides the new CPU I'm also using other thermal paste (Arctic Silver 5), but this shouldn't change the temperatures a lot: maybe 1°C or 2°C.
Next I've applied the recommended Intel settings from Ken (Intel support), which can be found back in the topic mentioned before (https://communities.intel.com/message/260210#260210). You can find a summary of the proposed settings in this official Intel document: Troubleshooting Intel® Core™ i7-4790K / i5-4690K overheating
2 changes I've made on my Gigabyte UD3H mobo are:
- I've put the VCORE voltage on 'normal' instead of manually adjusting it (because otherwise the voltage remains all the time the same instead of dropping when idle). Instead I've used a negative offset of -0,060V. This seems to run stable, however I didn't do long duration tests yet. But I didn't have any system crashes during testing yesterday evening, nor in idle, nor in stress. It might be even possible to decrease the negative offset even further (-0,070V or maybe even -0,080V).
- I've activated the XMP1 profile of my RAM. This could increase the power usage a bit (and hence also the temperatures), but since I am using Crucial Ballistix DDR3L memory running @ 1,35V (even when activating the XMP1 profile!) I don't expect any (significant) negative effect.
After applying these changes I've notice that the CPU speed is limited to something between 4,10 and 4,20 Ghz instead of the default 4,4Ghz (with default BIOS settings). These new values are actually correct, as 4,4 Ghz should, regarding Intel specs, only be achieved when only 1 or 2 cores ares stressed, not when all 4 cores are stressed as with Prime95 Small FFT's. (I didn't do any single core stress test yet.)
The temperatures I'm getting with these settings are even better. After running Prime95 with small FFT's for a couple of minutes, I'm getting stable temperatures around 64°C!
Notice this is achieved with an aftermarket air cooler, not with the stock cooler. I am using a Thermalright True Spirit 140 BW cooler.
I will do some more testing and if everything seems to be stable, I'll forward my settings to Ken (Intel support) so they can add them to the official documentation mentioned here above. I'll also mark the link to this thread as 'correct answer', but keep in mind that it's a combination of a new CPU with this settings which solved my problems. Without the new CPU I would expect that the temperatures would be 10°C - 20°C higher.