I have Lexar DDR5 7200MHz 32GB CL34 RAM (LD5U16G72C34LA-RGD) that I originally bought for a 14700K build because I heard high RAM speeds work better with Intel processors. Now, I'm planning to switch to a 9800X3D setup and I want to know if this RAM will run at full speed. Additionally, what kind of motherboard do I need? Is an X870E suitable? I can't return the RAM since I've had it for a while, and I really don't want to sell it.
1 Answer
Whether this RAM will run at full speed really depends on a couple of factors, mainly the quality of your silicon and how well you can tune the memory. Generally, it's unlikely that just enabling EXPO will get it to work at 7200MHz. Most 9800X3D users recommend 6000/CL30 timing as a sweet spot, which is usually sufficient. Given that you already own the RAM, you might as well just use it. If you find you need help with tuning, subreddits like /r/overclocking could be a good resource.
It's unfortunate that EXPO might not work seamlessly. I haven't gotten the 9800X3D yet either, so testing is out for me. I was hoping setting it up would be as easy as clicking XMP on a 3200MHz DDR4 stick. By the way, I've heard that X870 motherboards provide better memory support than X670; is that accurate?