N7 Core i7-8700K Custom PC
Modded Phanteks P400S case with Mass Effect N7 scheme and better air flow.
Kraken X62 and additional 140mm Noctua fans keep the system cool at nominal 4.7GHhz. Also runs happily but slightly warmer at 5Ghz.
Fan Configuration. So I actually started this build back in November 2017 when the i7-8700K first became "available". Since then I have been tweaking the fan configuration until where it is shown in the pictures. The general intention is to intake cold air from the front and bottom, run it over the components and exhaust from the back and top. Originally I had both Noctua fans blowing up and out of the top of the case but the one closest to the front was blowing cold air out so seemed of little value. Therefore I moved this 140mm fan to the inside side of the X62 blowing directly out across the 1080Ti. I also took the second Phanteks 120mm case fan and mounted it to the underside of the red PSU shroud at the bottom. This is sucking cold air from the front (from the underside of the shroud) and blowing it directly up at the hot 1080Ti. The final Phanteks 120mm fan is simply exhausting from the back of the case.
Temps. The i7-8700K @ 4.7Ghz runs at around 58C while being torture tested in Prime 95 (max heat mode) on all cores for a length of time. This is roughly 5C cooler with the front panel mod than without it and similar to running with the front panel off altogether and just the Phanteks magnetic filters in place over the front 140mm Kraken intake fans. I spent quite a bit of time down volting the CPU as this made a huge difference to it's temperatures. The fans are barely audible in this mode. None of the software or games I run (Mass Effect Andromeda, Fallout 4, Fortnite) get anywhere close to maxing out the CPU so it seems a bit unnecessary to run at 5GHz. Nevertheless, at 5Gz, the CPU needs more voltage, the temps rise and the fans speed up to a level I can hear them. A prime 95 torture heat test results in around 69C, but admittedly only after 30 mins or so.
So the CPU is cool. This is not always true for the 1080Ti. This is often hits 100% loading in games with the settings at ultra and operating near the 140Hz GSync limit of the Acer XB270HU 2560x1440 monitor. The 1080Ti hits around 78C and can make the glass directly adjacent to the fans quite hot. This is why I've currently got both the Phanteks 120mm blowing cold air at it from the bottom and the 140mm Noctua fan blowing across it from the side. The result is that the glass temp are back to warm and the 1080Ti fan speeds are lower.