I built my PC about a year ago and recently someone pointed out that I might have my GPU in the wrong PCIe slot. Right now, it's installed in the bottom slot, but they suggested it should be in the top one. I looked at the manual, and to me, the slots seemed identical, which left me a bit confused. My motherboard is the B650M PG Lightning WiFi, and the GPU is an AMD Radeon RX 6750 XT. I just want to make sure I'm using the best slot possible for performance. Thanks for your help!
3 Answers
According to your manual, the top slot is PCIE1 (PCIe 4.0 x16), which is meant for graphics cards. It provides significantly higher speeds—about 64GB/s—compared to the bottom slot's 8GB/s. If your GPU is in the bottom slot, it's likely experiencing a 50-87% performance reduction. It’s best to keep it in the top slot for optimal performance.
You definitely want to use the top PCIe slot for your GPU. The bottom slot is only PCIe 3.0 and has 4 lanes compared to the 16 lanes of the top slot. It might work, but you won't get the best performance that way.
Always put your GPU in the top PCIe slot! The bottom one is slower and can limit your graphics card's performance.
Thanks for the info! How can I tell the difference between the slots next time? The manual indicates both are PCIE1, and I assumed they were the same. Is it just common sense that the top slot is usually better?