Multiple M.2 Drives
Multiple M.2 Drives
Hello, I'm looking to install two WD Black Sn850x 1TB drives on an MSI Pro Z790. I plan to use one for programs and another for games. The CPU is an i7-13700K. I heard this might affect GPU performance, but I didn’t find a clear answer and some discussions were quite old. My question is: Will adding two of these drives impact the performance of a 4070Ti? Thanks.
It doesn't affect GPU performance. The two standard slots are set up differently—top for CPU, bottom for chipset. For instance, with a 13600K, the CPU has 20x lanes of PCIe Gen 4/5, x16 for GPU and x4 for the SSD top slot. This means an SSD won't slow things down. Because the GPU links to the CPU, the chipset offers ample bandwidth for SATA devices and the SSD. Some boards might need to turn off certain SATA ports to fit the SSD; review your motherboard specs for more info.
Varies with your processor, but it should work. Most modern CPUs now offer up to 20 PCI Express lanes—often a direct x16 connection to the GPU and at least four lanes for SSDs (PCIe 5.0 x4 M.2 slot). Other SSDs may route through the chipset or a doubler, which can be slower but won’t impact your GPU. Place your operating system drive in the PCIe 5.0 M.2 slot and your game drive in any available slots.
The OS drive doesn’t require the quickest speed; placing it in the top slot makes more sense since the fastest SSD should be there. With direct storage, the top slot would perform better for games or heavy tasks. You won’t notice a difference between slow and fast SSDs in the operating system, so there’s no need to use the fastest one just for OS purposes.
I agree with the assessment, though I won’t claim my response is wrong. It would be better if the OS storage connected directly to the CPU rather than via the chipset. (Yes, the OS drive doesn’t require the highest speed, but minimizing latency is crucial for a responsive system—even with direct storage, games can’t run smoothly without OS.) The user can set up game support for direct storage on the OS drive while keeping other drives for games that don’t need it. Since both are identical SN850x models, it really doesn’t matter which one you choose. The main concern is whether the drives will affect GPU performance. The answer is no. Reason: 13th Gen supports only x16 PCIe 5.0, but the SN850x uses PCIe 4.0, so all lanes are usable. If a PCIe 5.0 drive comes later, it won’t impact things because even today’s 4090 struggles with full PCIe 4.0 bandwidth. The bottleneck would appear long before you need true x16 speeds. Difference between latency and bandwidth: Latency is the delay for data to travel from SSD to RAM, while bandwidth refers to how much data can be transferred simultaneously.
But will the performance gap be noticeable? When I set up Windows on the M.2 CPU and put games and programs on the chipset M.2? Will the games load more slowly? Thanks for asking—this might not sound very smart, but I haven’t really explored those drives yet.