AMD quietly throttles clocks, PCIe 5.0 support on Ryzen "Phoenix" Zen...

AMD quietly throttles clocks, PCIe 5.0 support on Ryzen "Phoenix" Zen 4 APUs

Back at CES 2023 earlier this year in January, AMD, alongside several new products, announced its new Zen 4 mobile APUs as well. The reveal consisted of the Pheonix and the Dragon Range lineups. The Phoenix APUs were expected to bring 3GHz clock speeds to integrated graphics (IGP) and which could have meant that desktop counterparts, which would be released later, could have taken those clocks even higher.

Lisa Su showing off Dragon Range APU

However, it looks like the 3GHz RNDA 3 iGP core clock, which was listed previously on AMD's site has now been altered. Spotted by Twitter user Bionic_Squash, AMD has seemingly and quietly lowered the Radeon 780M's core clock speed on the Ryzen 9 7940HS. While the previous clock was 3,000MHz or 3GHz (surprisingly similar to those 3Ghz rumors before Radeon 7900 series was officially revealed), the 780M is currently rated at 2.8GHz or 2,800MHz, which is a 200MHz reduction.

Radeon 780M earlier clock 3GHz

Radeon 780M new clock 2.8GHz

Throttled clocks have not only affected the flagship 7940HS though, as other Phoenix SKUs, like the AMD Ryzen 7 7840HS, also see reduced clocks by 200MHz. Overall, it looks like all Radeon 780M IGPs have been stifled by 200MHz due to some reason, probably because the graphics portion of the APUs are unable to hit such clocks under the allotted TDP and voltages.

Another area where Phoenix has faltered is PCIe support. Back when AMD began teasing Phoenix, the company had claimed that PCIe 5.0 support would come to the Dragon range, as well as Phoenix. Here's an image of a slide that showed such features:

However, things did not turn out that way as Phoenix had to settle for PCIe 4.0 only. Perhaps AMD had felt that the Dragon range, which is geared more towards performance, would benefit much more from it.

Source: Bionic_squash (Twitter) via Andreas Schiling (Twitter)