I7 7700k Delid or Not to Delid

Guys,


About Prime95:

Do not use Prime95 versions later than 26.6 on 2nd through 7th Generation i3, i5 or i7 CPU's, which all have AVX (Advanced Vector Extension) Instruction Sets. Prime95 versions later than 26.6 run AVX code on the CPU's Floating Point Unit (FPU) which causes unrealistic temperatures up to 20°C higher. The FPU test in the utility AIDA64 shows similar results.

AVX can be disabled in Prime95 versions later than 26.6 by inserting "CpuSupportsAVX=0" into the "local.txt" file in Prime95's folder. However, since Core temperatures will be the same as 26.6, it's easier to just use 26.6. AVX doesn't affect Core i 1st Generation, Core 2, Pentium or Celeron processors since they don't have AVX Instruction Sets.

• Prime95 v26.6 - http://www.mersenneforum.org/showthread.php?t=15504

Recent motherboards address the AVX problem by providing Core speed multiplier offset adjustments in BIOS. Asus RealBench runs a realistic AVX workload, and is an excellent utility for testing overall system stability, whether you're overclocked or not.

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


About delidding:

In my opinion as an i7 overclocker, I believe that 2nd Generation Sandy Bridge was the last Intel mainstream processor that was thermally well behaved, consistent and comparatively predictable due to a soldered IHS. Disappointingly, Intel's 22nm and 14nm processors require delidding in order to provide overclockers with thermal behavior similar to 2nd Generation and earlier processors.

Keep in mind that when reviewing Thermal Specifications in the Datasheets, Intel uses engineering samples with soldered Integrated Heat Spreaders for testing and developing specifications. The Datasheets do not reflect the poor thermal performance of retail samples.

However, Silicon Lottery - https://siliconlottery.com/collections/all/products/delid - is a company that tests, bins and sells delidded "K" CPU's, so you can by a 7700K tested at 5.0 GHz without having to wonder about what you're getting. They also offer delidding services, and give the following figures on how much Core temperatures at 100% workload are improved by de-lidding:

7th Generation ... Kaby Lake - 12° to 25°C
6th Generation ... Skylake - 8°C to 18°C
5th Generation ... Broadwell - 8°C to 18°C
4th Generation ... Devil's Canyon - 7°C to 15°C
4th Generation ... Haswell - 10°C to 25°C
3rd Generation ... Ivy Bridge - 10°C to 25°C

boredboy94,

You can safely de-lid by using the Rockit 88 De-lidding Tool - https://rockitcool.myshopify.com/ or if you don't want to delid yourself, then just send your 7700K to Silicon Lottery. They do a professional job and have quick turnaround times.

Like lumineZ, my personal rig is a delidded 7700K. Before delidding, Core temperatures were ridiculously high into the 90's.

After delidding with Liquid Ultra under the IHS and MX-4 under the cooler:

5.0 GHz at 1.363 Vcore, 72°C Core temperatures with Prime95 v26.6 Small FFT's at 22°C ambient, Cooler Master TPC 812 Push-Pull high-end single tower air cooler. Idle temperatures 25° at 22°C ambient. Quiet fan curves provide gaming at ~ 55°C in a modded Antec 902 V3 with clean cable management.

As a result of delidding, a 7700K overclocked to 5.0 GHz can achieve good Core temperatures on air cooling.

CT

SumTingW0ng,

On behalf of Tom's Moderator Team, welcome aboard!

Intel tests their processors under carefully controlled conditions at 100% TDP. Prime95 version 26.6 Small FFT's is ideal for CPU thermal testing, because it's a steady 100% workload with steady Core temperatures that typically runs Core i variants with Hyperthreading and Core 2 processors within +/- a few % of TDP. No other utility so closely replicates Intel's proprietary test. This is also the utility that Real Temp uses to test Core temperature sensors.

Although AIDA64's CPU test is a steady workload, it's far below TDP, which is insufficient for thermal testing. All other AIDA64 CPU test combinations are fluctuating workloads which are OK for stability testing, but again aren't well suited for thermal testing. And of course, AIDA64 is not Freeware, so the Trial version expires.

You might want to read this Sticky: Intel Temperature Guide - http://www.tomshardware.com/forum/id-1800828/intel-temperature-guide.html

See the Charts in Section 12 - Thermal Test at 100% Workload.
A steady 100% workload is crucial for thermal testing.

Once again, welcome aboard!

CT

So is ASUS Realbench v2.54 latest consider to be a good free tool for overclock stability test? Consider ASUS Realbench push my CPU 6C higher than Prime 95 V26.6 .

Also, I can confirmed Aida 64 FPU, OCCT AVX, or the latest Prime 95 sky rocket my CPU up to 90C roof in less than 10 secs.