I'm building a setup with an ASUS x870-A motherboard and a Ryzen 9 9950X3D processor. My plan is to use a Gen 5 M.2 drive as the primary drive, and once it's available, I want to add another 8TB Gen 5 M.2 as a project drive for my work files. Additionally, I'll have a 3rd drive, a Gen 5 M.2 8TB Western Digital, for backups. I currently have everything set up and it's running smoothly with a Gen 4 WD drive and a Samsung 9100 for my main storage.
However, I'm confused about whether I can properly configure everything to run at full speed. The manual mentions that using M.2 slot 2 will limit my top PCI slot from 16x to 8x, which complicates my planning. Here's what I'm thinking:
1. Have a Gen 5 M.2 in M.2_1.
2. Plan for a Gen 5 M.2 in M.2_2, but it will slow down the top PCI
3. A Gen 4 M.2 in M.2_3, but this disables the PCI G4 entirely.
4. Another Gen 4 M.2 in M.2_4.
I want to confirm if it's better to keep my GPU in the typical top PCI slot while simultaneously using the M.2 slots effectively, or if using the lower PCI slot would impact performance in any way. Also, I'm realizing that my motherboard might limit my options for running both a second Gen 5 M.2 and my graphics card effectively. I want to make sure I have the best setup for gaming and some light fluid calculations.
3 Answers
You should use M.2 slots 1, 3, and 4 and keep your GPU in the top PCI slot where it belongs. The second Gen 5 M.2 can only go in slot 2 without compromising your GPU performance, so it's wise to keep that in mind. Putting it in slot 2 is going to limit your GPU to 8x, and that's something you may not want to risk for the sake of faster storage. Stick with the recommended layout for best performance!
You're looking at a compromise here between speeds. Since there's only one PCIe 5.0 lane available, and the second one is 4.0, you're right that if you plan to run both, you'll inevitably have to cut corners somewhere. The 4070ti will work on 4.0, sure, but you’ll be bottlenecking it. If performance matters, I’d consider upgrading the motherboard to gain more PCIe lanes for your setup.
Thanks for confirming what I suspected! It'll still be a big upgrade from my current setup, but exploring motherboard options is definitely on my to-do list.
Just a side note, the layout of your slots can also influence your cooling. Some boards have the top x16 slot moved slightly to allow airflow patterns or to fit an m.2 slot better. Consider that when planning your build!
That’s a really good point! I hadn’t thought about cooling. I’ll definitely check the clearance and airflow when I finalize my setup.
Totally agree! I was also excited about having two Gen 5 ports, but it turns out you can only use one without affecting your GPU performance. It's frustrating, but the first slot is usually the best for your graphics card.