8700K delid temps
8700K delid temps
Hello everyone,
My main concern right now is whether the temperatures are acceptable and meet expectations. Would they be better?
I performed a jump test and delidded my 8700K. It’s a fairly average CPU compared to the impressive ones people claim to have won. My focus isn’t primarily on the original clock speed, but on the temperatures and how I set them up correctly. There are many online tests about delid, but few are well-documented—so you really can't be sure what specific procedures people use, whether they turned off AVX, or what BIOS settings were applied, voltage levels, etc.
I’ll begin with the configuration and components, then attach a couple of screenshots. I used a standard test for p95/Coffee Lake OCs: 1344K Inplace FFTs with AVX disabled at 1.35V manual voltage inside the BIOS, making it straightforward to replicate.
Specifications: 8700K delidded, Conductonaut on die and back of IHS, as thin as possible. Applied clear nail polish on the four contacts near the die. Used a light reseal with Reinzosil sealant for high temperatures (though I can't really suggest it—this forms a very thin layer that's hard to clean; scraping doesn’t work and isopropyl alcohol 99% or acetone won’t dissolve it). Kryonaut placed between IHS and the cooler coldplate, using a small amount, spreading it as much as possible.
Ambient temperature: 24°C.
Cooling setup: Meshify C case, 4x140mm Noctua PWM fans (2 intakes, 2 exhausts), 1x120mm exhaust at the back, Noctua D15S cooler with an additional 120mm Noctua PWM fan on the front.
During testing, the fans operated around 60-75% (about 1500rpm for the 120mm, 1000rpm for the 140mm).
The motherboard is a ****ty 4-phase VRM MSI Gaming Plus. I haven’t noticed it throttling even with up to 165W power on the CPU. It’s essentially the same VRM as on the MSI Z370-A Pro, which der8auer reviewed in a video—he was able to OC it to 5.1GHz without a fan on the VRM. My own VRM temperatures hover around 80°C, peaking at 92°C. I personally wouldn’t recommend exceeding 150W through the VRMs.
Due to the motherboard’s VRM and the significant increase in power draw with AVX2 and Prime95, I can’t run SmallFFTs using AVX2. My CPU isn’t ideal for this purpose and seems to need around 1.33V–1.34V at 4800MHz if AVX2 is enabled. At 5GHz it might require 1.4V for full stability.
Testing results:
1. At BIOS 1.35V, 50x multiplier, no AVX offset, 44x Uncore.
- Peak temps: 75°C max, average 71°C per core/package. Power draw peaked at 144W.
2. At Realbench (last version), AVX test, GPU included.
- 15-minute stress test, 8GB RAM used.
- Max core temp 77°C, average 73°C per core/package. Peak draw 134W.
Spoiler:
Test 2: Realbench (likely an AVX benchmark using the GPU).
- 15 minutes, 8GB RAM.
- Max core temp 77°C, average 73°C per core/package. Peak draw 134W.
Spoiler:
If you attempt to match my setup, it’s probably not too low a voltage—my 8700K becomes unstable below 1.32V@5GHz, so I can’t verify that. Also, testing P95 with AVX2 above 4.8GHz is out of reach because of the VRMs and the high voltage needed for AVX2 stability.
Thank you for reading. I’m just checking if my Conductonaut application was correct—mostly it’s unchanged, though.
Bonus images show liquid metal affecting the IHS after two days and the extremely thin silicon pellicle left post-sealant; cleaning the IHS is nearly impossible. The acetone and isopropyl alcohol didn’t reverse the reaction. The LM appears very sensitive even with nickel-plated IHS.
The delid is doing well, looks great. The 8700k model performs adequately if you require 1.35V in BIOS settings. It offers a 50x boost, no AVX offset needed, and 44x Uncore support. Only 17% achieve 5GHz with AVX at 1.425 volts according to silicon statistics. Prime95 temperatures indicate ample headroom. VRM temperatures sit between 80°C and 92°C, peaking at 92°C. Although high, I’ve experienced 98-104°C VRM temps for over five years without problems, especially with good airflow. In Prime 95 small FFTs, it dropped to 98°C in the 95 model. A monoblock covering both CPU and VRM could help reduce VRM temperatures if available for your board. Here’s a relevant link:
https://www.overclockers.co.uk/ek-w...
Ensure you check compatibility before purchasing.
SL probably tests with AVX2/SmallFFTs, other than that I can't explain their voltages. It's understandable to be honest. I played around quite a bit with this chip, within the limits of my motherboard, as at the time it was a large purchase of many components and I had to save on stuff I wouldn't otherwise. With undervolting, the chip was never fully stable until I got SmallFFTs with AVX2 stable for 12hrs or so, there was always that one app or game that would crash 2-3 time/month, and even the very rare BSOD. Once I passed those 12 hrs of AVX2 hardcore stress, there were no other game crashes or BSODs at all, for months.
Water cooling will probably wait a lot for my case. I've had quite a few friends that had weird (biological?) disgusting growth inside their AIOs or loops, and a few even had leaks that killed parts of their PC. I'm way too risk averse to go into it.
As for the chip itself, I can't really stresstest the 5GHz OC properly, there's no way I can draw the 250W I've seen for others with SmallFFTs/AVX2. At around 170-180W the VRMs go above 100-105 and while there's no throttling of any sort, it's also not comfortable to watch things get so toasty. I used 1.35V fixed because I know many just dial that in and run their PCs like that with the 8700K. The CPU is fine with 1.33V for p95/1344k inplace/no AVX, at least fine for 3hrs. Realbench also passes fine. But LinX/LinpackX, OCCT with AVX or P95 with AVX fail at 1.33 (and 1.35) almost on the spot.
But yeah, worth noticing that even with the 1.4V for 5GHz, SL still used the AVX offset, so that's basically a 4.8GHz OC when you run AVX. Even at 4.8GHz, with 1.4V I'm sure they hit 200W power draw figures, the Coffee Lakes are insanely power hungry once you OC them.
I've experienced leaks that caused components to fail. Those who use water cooling are aware of the dangers. If you think the VRM is too hot, you're making a wise choice. You might manage the power consumption in BIOS, which restricts tools like prime95 but doesn't affect games as much.