LogFAQs > #965402134

Okay. Here's the lowdown. You can get RAM that have different speeds, and the faster speed will underclock to the slower speed. That's been a thing for years. What has changed is the idea of memory overclocking and tuning. Used to be you had to fiddle with the switches manually in the BIOS, then run Prime95 to test and validate your configuration. Nowadays, most kits will come with a factory dialed in overclock that you activate in a menu in your BIOS. You run the risk of creating system instability if you get a slower kit of RAM, because now your BIOS will read that you have two different kits of RAM with two different memory profiles that can be activated. Your faster kit can probably underclock to the slower memory profile, as it usually has tighter timings (CAS Latency), but you do need to be relatively comfortable with going into your BIOS to adjust these settings.

If you have literally no idea what I'm talking about, then just get a kit of RAM that runs at the same memory speed that you have currently.