According to tests conducted by Jarrod, the use of loose memory timings reduces the performance of the newly launch Radeon RX 6000 mobile GPUs by as much as 20%. This issue was noted with the ASUS Strix G15 as well as the Lenovo Legion 5 Pro. The latter came with dual-channel DDR4-3200 memory, but both the primary and secondary timings were pretty loose, with a tCL value of 22 and tRC of 74. However, the YouTuber didn’t fiddle with the primary timings, tightening the secondary timings such as the tRRDS, tRRDL, and tRFC by nearly half. (Ultram)
This resulted in a performance gain of nearly 20%, with the average frame rates in Shadow of the Tomb Raider going from 102 FPS average with the default memory to 121 with the tuned one. Furthermore, connected to an external display also resulted in a fair bit of extra performance. This is because even when using the dGPU, the frames pass through the iGPU which results in increased latency and therefore, slightly lower performance.