The original post: /r/amd by /u/RyanOCallaghan01 on 2024-09-18 02:22:35.
Hi all.
Upon hearing about the new AGESA which supposedly “fixes” the high inter-CCD latency of dual-CCD Zen 5 CPUs, I decided to download the latest beta BIOS version for my Asus X670E Hero (version 2401).
Things were off to a good start when I measured the before and after using the MicroBenchX Core to Core latency program. I used the results to create the following latency heatmaps:
However, I ran a quick test using a CPU intensive scene in GTA V using CPU core affinity to assign 2c/4t using just a single CCD, or one core from each CCD. Performance absolutely fell apart when splitting between CCDs:
I do not have a similar screenshot from the previous BIOS version, but I did run the same test - despite the much higher inter-CCD latency according to the benchmark, using the same 2 CCD affinity on the previous BIOS version only resulted in a performance impact of roughly 6% compared to the single CCD. The old BIOS version produced a remarkable result bearing in mind that the second CCD clocks lower than the first (up to 5.35 GHz vs 5.625 GHz) and the supposed ~150% higher inter-CCD latency.
As it stands, I will definitely be updating my BIOS again and either (optimistically) settling for the best of both worlds if another version would rectify this, or rolling back and sticking to the previous version for the superior real-world performance.
Thank you for reading, feel free to share any thoughts or input you may have on this topic - I would also much appreciate it if anyone has any results of their own to share.