14900K PCIe Lane Configurations on Z790

[99in1]

Hey all, 

I've recently built a new PC with an i9 13900K on the Gigabyte Aero G Z790 Motherboard. I have a Gen5 SSD installed (capable of speeds up to 12000mbps) but find I need to bring down my main PCIe slot down to x8 in order for the SSD to run at full speed.

I wondered if upgrading to the 14900K would solve this issue - I've compared the specs on the intel website and they look the same regarding PCIe lanes:

I asked Gigabyte if the Aero G will allow me to run the 14900K to allow Gen5 speeds with both the Graphics card (@x16) and the SSD (@x4) and they said it DOES. Which I was kind of surprised with. 

In before the comments about "you dont even need those speeds for a GPU - just run it at x8" etc etc. I know this but I'm doing my best to future proof this for the highest end RTX50 series card when it comes out and I'd like THAT to be running at PCIe5x16 when it releases.

Am I able to get any definitive information here about whether the 14900K will make any difference or would I need to wait for 15th gen to take advantage of more PCIe lanes? (meaning i'd need to get a new motherboard... sigh)

[DeividA_Intel]

Hello 99in1,  

Thank you for posting on the Intel® communities. I understand your concern about the lane support and capabilities for the Intel® Core™ i9 processor 14900K.

I will proceed to check the issue internally and post back soon with more details. 

Best regards, 

Deivid A.  

Intel Customer Support Technician 

[DeividA_Intel]

Hello 99in1, 

Thanks for your patience. As you noticed, both CPU generation has similar capabilities and if what you want to set is something that used to do on a 13th-generation CPU, you can do it with a 14th-generation as long as the motherboard supports it too.

You can check with the motherboard manufacturer (one more time) to confirm.

Please keep in mind that this thread will no longer be monitored by Intel.  

Regards,  

Deivid A.  

Intel Customer Support Technician  

[JessieTech]

The answer is no. The cpu is identical to the 13900ks. Both only have 16 gen 5 lanes and 4 gen 4 lanes going to the cpu. Even with a gen 4 gpu, it's still going to use 16 of those lanes. Leaving only 4 gen 4 lanes directly to the cpu. If they had made all 20 cpu lanes gen 5, the answer would have been yes. They could have also included 4 gen 5 chipset lanes to get the same result. The amd has all gen 5 lanes and more of them but the intel chip runs much smoother, much better memory controller and can be pushed much harder. Amd picks one thing to do better and 20 things worse. Like how amd gpu's have displayport 2.1 but nvidia has 1.4 yet the nvidia cards are twice as powerful. Amd tricks you while intel just misses our on the obvious. They must not have many real pc nerds making decisions. If I were in the room, this would have been an obvious upgrade to do.

[BoredNerd]

Tried 5090 sample board on z690 extreme by Asus. Because I am running 4 m.2 my pcix5_1 aka main GPU slot runs at 8x. I tried removing one of the m.2 to run that main pcix at 16x and just like with my previous unit rtx 3090 EVGA retail unit runs at exactly same speeds as x8 , exactly. I'll tell you more at 3dmark 3090 runs at little higher score when using 8x. Less than 1% but still higher.

Good luck.