The B650 chipset doesn't officially support the PCIe 5.0 bandwidth for the PCIe x16 slot but GIGABYTE B650 motherboard BIOSes still offered the option, irrespective of its non-functional state.
GIGABYTE Reportedly Removes the PCIe 5.0 Option from B650 Motherboard BIOS Via BIOS F35
It's unusual to see the PCIe 5.0 option for the PCIe x16 slot for graphics cards on the B650 chipset motherboards but apparently it was available in the BIOS, at least as per the report by the Redditor u/Rejumi. The user wrote on a Reddit thread that after updating the BIOS from F34 to F35, he lost the PCIe 5.0 option in the BIOS for his graphics card and now his RX 9070 XT runs only at PCIe 4.0 x16.
It's interesting to see that at the time of writing GIGABYTE has removed the F35 BIOS from the support page of the affected motherboard, the B650 Gaming X AX V2 rev, 1.x, and has instead put the F36 in its place. So, you can either go with the F34, which has the PCIe 5.0 support enabled for the primary PCIe x16 slot or you may update to the latest F36, which shouldn't have PCIe 5.0 option in the BIOS. Either way, it doesn't matter because by default the PCIe 5.0 doesn't work on the B650 chipset motherboards and it will offer the same speed as the PCIe 4.0.
The Redditor said that he saw some regression in performance but it could be likely due to various other parameters, which get affected in BIOS updates. Now, as far as the PCIe 5.0 support on B650 is concerned, GIGABYTE has never advertised this for its B650 lineup. As per the Chiphell user "Hugable carrot" (via @unikoshardware), there were a lot of complaints with GPUs running at PCIe 5.0 on GIGABYTE B650 motherboards. Therefore, disabling the PCIe 5.0 is likely a measure to fix the bugs.
Nonetheless, the PCIe 4.0 x16 interface is sufficient even for the flagship NVIDIA and AMD GPUs from the current lineup, and one shouldn't be worried about the performance if they own a B650 motherboard from GIGABYTE or any other motherboard maker. However, the problem starts to surface when the PCIe lanes are reduced from x16 to x8, which has shown performance impacts on 8 Gigabyte GPUs such as GeForce RTX 5060 Ti.
News Sources: Reddit, Computerbase
About the author: Sarfraz Khan is a hardware reporter with a focus on PC components and the builder community. With years of experience writing about PC hardware and laptops, his work has been featured on several reputable technology publications. Sarfraz's hands-on experience is demonstrated through his first-person accounts of using and comparing different hardware configurations, providing practical and relatable insights for everyday users. His technical analysis is respected by peers in the enthusiast community and has been cited by specialized hardware sites such as Germany's Igor's Lab.
Follow Wccftech on Google to get more of our news coverage in your feeds.
