For our manual overclocking tests, we used AMD's performance tuning tool within the Adrenalin driver. Our best results are as below.
Undervolting is absolutely crucial for the 7900 XTX if you want to improve performance, and at 1060mv, we were able to push the core to 3000MHz, and set the memory to 2750MHz.
This saw real world GPU clock speeds increase up to 2853MHz, a 13% improvement over stock frequency.
As you can expect, couple the GPU overclock with the memory overclock, and we saw our frame rates improve by between 9-10% in the titles we retested, which really isn’t bad at all. Admittedly It’s not a massive game changer and the 7900 XTX will still be slower than a stock RTX 4090, but as overclocking goes on modern GPUs, it’s pretty decent.
The only downside is that power draw increases further, now averaging just under 437W, which is a 17% increase over stock.