Discussing the impact of several NVMe drives on GPU speed
Discussing the impact of several NVMe drives on GPU speed
Hi everyone I have a 4070 Ti GPU, an i5-13600K CPU and a 2 TB Kingston KC3000 NVMe drive connected to an ASUS PRIME Z790-P motherboard. I’m thinking about adding a smaller drive for booting Windows. At first I thought about another NVMe drive but after researching (this is my first build) I’m unsure if it would impact the GPU performance. My current idea is that the GPU uses 1x16 PCIe 5.0 lanes and the NVMe drive uses 1x4 PCIe 4.0 lanes. If I add another NVMe drive, the GPU would then use 1x8 PCIe 5.0 lanes while each drive takes 1x4 PCIe 4.0 lanes. How does cutting down the PCIe lanes affect the GPU speed? I’m really new to assembling PCs so any advice would be greatly appreciated!
This won’t impact GPU performance since it operates through the chipset lanes, not the GPU itself. I’ll be getting an NVMe SSD for this. The board is configured to keep the GPU connected via an X16 link regardless of the M.2 drives installed.
I understand the diagram you're looking at. In this setup, PCIe lanes are typically reserved for GPUs to provide them with their own bandwidth. If a GPU shared those lanes with NVMe drives, it could impact performance. Adding more drives would likely reduce the available lanes, potentially degrading overall speed.
The connection between the CPU and chipset mainly depends on the SME PCEI Gen 4 X8 link, which allows around 16Gb/s. Usually you don’t overload all chipset features at once, so it shouldn’t cause issues. Generally, switching from 16 to 8 lanes on your GPU has only a minor effect. Some boards can split the 16 lanes into two 8 lanes, but yours doesn’t do that.
Those positioned on the DMI would experience longer delays, though this isn't significant for many uses where heavy storage access is required. It'll be okay.
It’s understandable you’re concerned about storage choices. Generally, smaller drives come at a higher cost per gigabyte. You’re also restricting future expansion options by sticking to the same PCIe lanes as a standard drive, which limits available space. Currently, top-tier 2TB SSDs are quite affordable—just a few hundred dollars in North America. In Canada last year, a 2TB NVMe was over $400 CAD, which felt steep compared to regular SATA options. Recently on Newegg, they were around $135, roughly equivalent to about $100 USD. That’s surprisingly close to the price of a basic SATA hard drive. On the flip side, if you’re not planning to expand much and don’t need extra capacity, creating partitions on your existing drive is a free way to organize files without affecting system libraries or performance.
Thank you! You're right to think about cost per GB. Using a smaller drive can save money. Regarding your second question, when you create a partition on one of your drives, only that specific area is erased if you reinstall Windows, not the entire drive. The partitions remain as separate entities.