[SOLVED] Best CPU for SLI/NVLink gaming (X299 vs Z390)

[wellerkd]

Hey guys,

just came across this awesome forum. I managed to preorder two Asus ROG Strix 2080 Tis for my new build. I was planning on a 9980XE + Asus Rampage VI Extreme, however I'm having second thoughts. This build is both for content creation (Adobe mostly) and gaming - I've been using a Mac Pro so far and I wanted to switch to a windows system in order to get back into gaming, so gaming performance is my main concern here.

The alternative is a 9900K, but I'd be out of PCI lanes with one GPU alone, let alone two. I'm planning on at least one additional M.2 SSDs, maybe two. I'd feel more comfortable with the X299 setup, but I don't want to end up with a build that can't handle upcoming AAA titles. I'm currently using 2x 1440x3440 displays @ 120Hz and will be playing both graphic intense AAA titles as well as some CS:GO and less demanding games.

Do I sacrifice a ton of gaming performance by going HEDT with the 9980XE? I understand that 16x/16x NVLink does not make a huge difference right now, but that might change in the future, no? Benchmarks are all over the place. Some suggest that 9900K has a 20FPS advantage in games like Far Cry @1080p and other show a difference of 1-4 FPS between the two CPUs @1080p.

I know that the 9980XE and it's mesh architecture and not optimal for gaming, but doesn't the increase in PCI bandwith even it out somewhat? Most sources just say that 9980XE is not for gaming, but how does it compare? Is it so much worse?

 

[feelinfroggy777]

At that 3440x1440p you are not gonna sacrifice any gaming performance with the HEDT. When you move up in resolution, the CPU matters less. The extra PCIe lanes wont matter much for the GPUs, but if you want multiple M.2, then the extra lanes will be needed.

Lastly, running 2080ti in SLI is a waste with your monitor. Even a 3440x1440p 120hz panel. One 2080ti will push that panel just fine. Once you get over 120fps, there is no difference. The only reason to go for 2 2080ti will be if you have a 4k/144hz panel. Plus, SLI is terrible. I ran 1080ti SLI for awhile and about half the games it does not work. I got tired of turning it off and on for certain games so that I would forget to turn it on during the games that supported it. Do yourself a favor and cancel one of your preorders.

And dont worry about running the games of tomorrow. Your rig will be as future proof as one can get.

 

[wellerkd]

At that 3440x1440p you are not gonna sacrifice any gaming performance with the HEDT. When you move up in resolution, the CPU matters less. The extra PCIe lanes wont matter much for the GPUs, but if you want multiple M.2, then the extra lanes will be needed.

Lastly, running 2080ti in SLI is a waste with your monitor. Even a 3440x1440p 120hz panel. One 2080ti will push that panel just fine. Once you get over 120fps, there is no difference. The only reason to go for 2 2080ti will be if you have a 4k/144hz panel. Plus, SLI is terrible. I ran 1080ti SLI for awhile and about half the games it does not work. I got tired of turning it off and on for certain games so that I would forget to turn it on during the games that supported it. Do yourself a favor and cancel one of your preorders.

And dont worry about running the games of tomorrow. Your rig will be as future proof as one can get.

Thanks for your response. I do have a follow-up question: is there a performance difference regarding a M.2 SSD via CPU lane (x299) vs. chipset lane (Z390)?

 

[feelinfroggy777]

In general, no there wont be a difference if you are using PCIe lanes from the chipset or the CPU. But technically the 9900k can only take 16 lanes of PCIe, no matter how you slice it up or where it comes from. The lanes created by the chipset still go through the CPU. But unless all the lanes are completely saturated, the system knows how to delegate out the data in the lanes are coming from the chipset or the CPU.

It is like a freeway. The free way only has 8 lanes, no more no matter what. But there are a lot of on ramps and exit ramps that flow traffic in the right way to maximize the flow.

So in the real world, you wont see a difference except perhaps in a simulated benchmark under certain circumstances (such as gaming and performing specific task on a NVMe drive). The odds of the freeway all backing up at the same time are unlikely and even if it does the data saturation is not static, so it would only be for moment.