What settings should I check in BIOS for using 2x8GB DDR3 RAM?

From what you've described, it sounds like your motherboard might not be set up to support both sticks together. First off, make sure you're using the slots recommended by your motherboard. Typically, they should be in the same color or paired slots for dual-channel support. Also, check if you have the latest BIOS version installed—updating it can sometimes solve compatibility issues. Lastly, if your BIOS is up-to-date and it still doesn't work, the new RAM stick might not be compatible with the one you already have.

I totally understand the struggle! If you're having trouble figuring out if your BIOS is updated, you can usually enter the BIOS screen when you first boot up—look for the BIOS version listed there. If it’s outdated, definitely follow the manufacturer’s site for details on updating it. Just a heads up, it’s crucial to have the right RAM sticks, as not all RAM works perfectly together even on older setups like DDR3.

It’s a good idea to update your BIOS if you're having issues with RAM compatibility. If you’re not sure how to do that, most manufacturers have detailed guides on their website. Check your motherboard model to find the latest version. Just be careful during the update process to avoid any mishaps. And remember, mixing RAM sticks, especially if they are from different brands or speeds, can lead to these kinds of problems. Ideally, you'd want them to match.