Gen 12 Intel i9-12900KS vs 11th Gen i9-11900K Hardware with a 3090 RTX, plus a Nvidia Geforce 4090 RTX, Nvidia 3050 + 980 GTX


 Got a 12th Gen Intel to go with my prior / other setup with a Gundam board and 11th Gen Intel.

Original post on the forums is here. Formatting likely better there as that is where this post was built from, then added for WordPress front page.

This post is the aggregation and conclusion of about a year of triage on my personal hardware with full details in the linked thread. Jump to the lead, if you have reboots with a high performance graphics card and modern Graphics Card, you may need higher than a 750 Watt Power Supply as was my case. I figured that out on August 4th 2023. So like, a year later.

Fixed this with a new Power Supply.  If you get reboots, make sure you have enough power.  I had a 750 W that worked for the 11th Gen but was reboot life on the 12th Gen.

I’m on a 4090 RTX in my 12th Gen with a 1500 W now.  Still also stable. ðŸ™‚

11th Gen and 3090 RTX has a 1000 W PSU now. :ninjawub:

​Specs for the 12th Gen Intel build ( as of 2023-09-26 ) :


System:  Micro-Star MS-7D30
CPU: Intel i9-12700KS
Motherboard:  MSI MPG Z690 FORCE WIFI (MS-7D30)  (all builds)
Memory:  109 GB free of 128 GB @ 4 GHz

GPU:  Nvidia 4090 RTX ( 24 GB )
Display:  5120 x 1440 – 32 Bit colors
OS:  Windows 11

Honestly so far, the 12th Gen has been a bit fucky to have good temperatures using Corsair H150i Elete LCD and H115i (dual 140 mm fans and radiator).  I have a 3090 that runs well but hot damn, long graphics card. By that I mean, most depth used in a case and I had to move radiator upward for depth for cases.  Angry 12th Gen Intel.

Original forum thread is here with more details. This is the abridged version over a year.

Edit! 2023-08-04:

Keep in mind I only recently resolved the reboots.  Power supply was too weak!
I had a 750 W PSU trying to run the 12th Gen and a 3090 RTX.  This works for an 11th Gen since that CPU pulls around 250 Watts give or take.  3090 will grab 350 W and a 12th Gen can pull about 350 W as well.

Fun fact as the 212 F was not causing reboots but is more due to poor contact with the default CPU Clip.  As I mention later in this thread, I added a 12th and 13th Gen CPU socket block to assist in an even mount.  Be cautious of over-clamping to not spread thermal compound out from between cooler and GPU, even with CPU support block installed.

Original post continues below:

Corsair Crystal Series 680X is my primary case for the 12th Gen.  I still have some airflow tweaks but main goals are re-gooping thermal paste.  For a nice thermal cap test, run benchmark.  I also learned Cyberpunk 2077 also has a benchmark now.  It’s in the settings in-game.

Typing this wave of post on the 11th Gen before I redo thermal compound again.  I saw the GPU price drops and things, went a little ham and got a 3090 RTX for $1350 instead of the $2000+ it debuted at in May of 2022.

The liquid smooth FFXIV Benchmarks are maddening.  Baby watches them with me as well.

Speaking on this GPU, check these dimensions. 318.5 x 140.1 x 57.78 mm 12.53 x 5.51 x 2.27 inches

Haha yeah, 330 mm is the max for the Corsair 680X case.  4000x says 360 mm GPU but I would think front radiators would be tight.  I moved mine to the top in the 680X case.

Off to operation.  Here are some UserBenchmark results from the 11th Gen Intel with a 3050 RTX in here.


UserBenchmarks: Game 85%, Desk 111%, Work 86%
CPU: Intel Core i9-11900K – 106%
GPU: Nvidia RTX 3050 – 74.7%
SSD: Samsung 980 Pro NVMe PCIe M.2 1TB – 453.7%
SSD: Samsung Portable SSD T5 500GB – 89.6%
RAM: Corsair CMH32GX4M2D3600C18 4x16GB – 109.3%

Peak Core i9 11900K Temperatures for package and Cores max was 155 F. / 68 C.

Collecting these from HWMonitor.

CPU Powers Package Max 195 W

Powers IA Cores Max 181 W 

Editing in to share below benchmarks with 3090 in the 11th Gen Intel setup.

Current run 9/19/2022:


UserBenchmarks: Game 252%, Desk 109%, Work 255%
CPU: Intel Core i9-11900K – 106.4%
GPU: Nvidia RTX 3090 – 243.6%
SSD: Samsung 980 Pro NVMe PCIe M.2 1TB – 450.3%
RAM: Corsair CMH32GX4M2D3600C18 4x16GB – 108.7%


Jumping ahead to once I got the Power Supply sorted in 2023-08:


 I got my thermals performing better but still see some 212 F / 100 C peak temperatures.  However, zero reboots. Been stable since last cooling work on 2023-08-07 (August).

Typical desktop / general use temperatures or light loads while web browsing temperatures on the 12th Gen Intel are 125 F / 51 C to 165 F / 74 C.

Installing the CPU Support block gave immensely better contact with the thermal block to CPU. My thermal applications were even, instead of like a third of the block not making good contact with processor as seen when I would check the spread on the block from prior install. Get one of those for sure if you see similar poor cooling. I was seeing huge spikes to 185 F / 85 C when under Idle and lower web browsing, before I replaced the stock CPU clip. Keep in mind for my use case, this was on 2 different Intel Z690 motherboards. (Asus and MSI)

If your GPU isn’t large, the 12th Gen reboot power supply issues are unlikely. When I put a 3050 GTX in my 12th Gen, it stopped rebooting. That is when I learned the power supply was root cause for instability. The cooling being higher with the higher Watt CPU is consistent on Corsair and Asus AiO kits as I tested that out on both and they performed right about equally, short of the Asus AiO being easier to make better CPU contact, before I added the mounting block.

Welcome to end of my mega thread triaging my main desktop. What a ride. 

When I got the bigger power supply in August ( 1500 W upgrade from a 750 W ), I also grabbed an Asus ROG 4090 RTX in the store because I was enamored Micro Center had it in stock.

There is an Evangelion version of the 4090 RTX now but it also costs $2300 last I checked. My $2000 stung enough and I think the Red Asuka card does not look as sick as the Rei Evangelion 3090 RTX. I will keep that one for secondary rig and crunching fun. That cart is too pretty. Granted it launched for $2000 asking price in May 2022 and dropped to $1300 in July 2022 when I picked it up.

Adding some current and final build photos for the 12th Gen Intel desktop too. I had plenty of time working case setups over the last year while tweaking this rig to stable. Also note, the 4090 RTX is even bigger and longer than the 3090 RTX was.

My case is the Corsair 680X RGB Crystal Series case. I actually have 2 since I got this white case and use my other black 680X case for the Intel 4th Gen i5-4690K that is for my Son to play with 😛 He has a 3050 RTX in there I took out of Wifey’s case since she does not game and the Intel GPU gives less hassles for audio out on Linux, as she is a Dev that does not game it up. Don’t get me started on Manjaro and typical Linux to Nvidia support or just like, general audio management and lol pulseaudio.