Ryzen 3900XT paired with InfiniBand fabric.
Ryzen 3900XT paired with InfiniBand fabric.
I assembled this machine about two years ago, and at that time the ideal setting for the infinity fabric was 1800. After a recent BIOS upgrade to version 4021, I'm curious if those changes affected the optimal values. My current build includes a Ryzen 3900XT, Asus TUF Gaming X570 Plus, Wi-Fi Corsair Vengeance 16x2GB DDR4 4000 CL18. RAM is at 3600 MHz and the infinity fabric remains at 1800. With a 4000 MHz RAM, should I lower the IF to 2000? It's been a while since I built it, mostly just assembling it, but I thought updating BIOS would improve things. Any guidance would be greatly appreciated!
1800 is a reliable level every Zen2 CPU should support. Only a handful can manage 1900, and I doubt any reach 2000, making it unsafe to exceed 1800. Staying at this setting avoids instability risks and eliminates the need for complex adjustments or tests.
It seems the CPU actually controls the Infinity Fabric speed. Previously I believed it was the motherboard, BIOS, and RAM speed, but now I realize the CPU might be the limiting factor. The last time I checked was almost two years ago, and it looks like I may have adjusted the settings higher—ram at 3800MHz, infinity fabric at 1900.
Thanks for asking! It’s unclear if there’s a noticeable performance boost when increasing the game clock from 1800 to 2000 or even further. It might be worth testing, but it’s uncertain if it’s truly beneficial. Consider sticking with 1900 unless you’re experimenting specifically for higher infinity fabric.
Keep it as is, you're almost at the maximum. Make sure all settings are locked to a steady pace in the bios—adjusting for both CPU and RAM speed so nothing runs on auto.
For gaming it doesn't matter, a stock 3900XT is sufficient for any game, I wouldn't be concerned about it.