Question about JBAT1 header for B450M PRO-M2 MAX
Question about JBAT1 header for B450M PRO-M2 MAX
I reached the decision that my motherboard is responsible for the BIOS problem. The manual shows a jumper cable should be used, but it doesn’t mention the 4-pin header on the board. I think the image suggests placing the jumper on the right two pins to clear the BIOS. My main issue is not seeing a BIOS screen, even though I know it’s not the graphics card—my tests on another system confirmed this. The only alternatives seem to be checking the CPU or assuming the motherboard has failed completely. I tried charging the CMOS battery for five minutes, which might be my final attempt. I originally took out my GPU to access a M.2 slot, but now the board won’t recognize any BIOS data, even though the M.2 was removed just for testing.
For future reference, JBAT1 (CMOS Clear Pins) consists of only two pins. The "Keep Data" diagram shows the pins not connected together, while the "Clear Data" diagram illustrates them linked via jumper caps (shorted). You don’t need to use jumper caps—simply short the two pins with a conductive tool like a flathead screwdriver. This setup appears to be a standard configuration, not a new system. As for the full specifications, please confirm if you need detailed technical data.
Based on my initial findings here, it seems the issue might relate to the motherboard. I tested the GPU on another PC and it worked there, so I’m trying to clear the CMOS by unplugging the 24-pin/8-pin and CMOS connections just to see if that helps as a last resort. It’s been confirmed to work, though I only attempted an M.2 upgrade and the BIOS didn’t load after resetting the GPU again.