The power efficiency of AMD’s Ryzen 3000 processors is often praised, especially if you compare it against that of Intel’s 9th and 10th Gen lineup. The higher-end Ryzen 9 parts can even have their TDP further reduced by a significant degree without imposing a significant performance penalty using “Eco Mode”.
However, when it comes to the Ryzen 4000 APUs (Renoir), it seems that the 65W TDP is a major bottleneck, especially in terms of graphics performance. The Renoir parts feature the 7nm Vega iGPUs with fewer Compute Units compared to the previous generation, but they still beat them by a haughty margin. These graphics processors, however, would likely be a lot more potent if the TDP of the APUs could be increased to 105W.
On the Weibo forums, well-known user WolStame has confirmed this by using a modified BIOS, unlocking the 88W power limit enforced in all Renoir desktop APUs. As per the user, increasing the maximum socket draw to 130W increases CPU performance by 6% while the GPU performance is boosted by a massive 32%.
Furthermore, if you’re using an air-cooler at the default 65W configuration, you’re losing out on as much as 40% of iGPU performance in the case of the 4700G. The loss on the CPU side is much less pronounced at 10%. This is likely due to the efficiency of the Zen 2 architecture while the Vega iGPU still being based on GCN continues to be a power-hungry chip.
The performance loss is much more significant in the case of the flagship, the Ryzen 7 4700G. When used with a 240mm AIO cooler, you gain 32% additional graphics performance on unlocking the 88W power limit while the 4600G gains just around 17%.