Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs compared to equivalent AMD Renoir APUs

[Redaktion]

Because of the inherent design limitations of the AMD Ryzen 4000U APUs, some benchmarks will favor the Intel Tiger Lake-U CPUs, but these results may not always reflect real-world usage scenarios.

https://www.notebookcheck.net/Here-is-why-LPDDR4x-4266-RAM-seems-considerably-faster-when-coupled-with-Intel-Tiger-Lake-U-CPUs-compared-to-equivalent-AMD-Renoir-APUs.480844.0.html

[JayN]

Well, perhaps the lowered ddr clocks  are necessary due to the raised GPU clock in Renoir.

I noticed some reviews of Renoir where dimming the screen was considered an acceptable optimization.   

[Agfsfhxzafhx]

 We'll see when reviews come

[john10072020]

Userbench? You should ban that benchmark/site even if it does, sometimes, post interesting results.

UserBench...... If AMD then final_score = score*0.75

[wow&wow]

Users only need to care and compare the use results, otherwise smart designs will be discouraged.

One smart design is Intel's using partial addresses, faster and less silicon, and nobody cares, even so-called reviewers and techies :-)

[AaR]

Intel CPUs have had dynamic frequency scaling for years now. Called SAGV. So I don't think you statement is true.

[JayN]

MCLK= memory clock, UCLK= memory controller clock, FCLK=Fabric clock

According to the twitter discussion,  if the CPU is in high power state,  AMD sets FCLK:UCLK:MCLK ratio to 1:1:1, all at 1333MHz, so all are synchronized for best transfer rate.

If GPU is in high power state, they raise MCLK to 2133MHz , but dial back UCLK and FCLK to allocate more power to GPU.  In particular UCLK to 1067MHz.

So ... looks like working around thermal issues with whatever levers they have.

[10basetom]

If an AMD laptop supports 4266 MHz LPDDR4X, where can one actually buy one to upgrade their RAM?

[Adröit]

If an AMD laptop supports 4266 MHz LPDDR4X, where can one actually buy one to upgrade their RAM?

LPDDR RAM is not upgradeable. It is soldered to the motherboard, be it on laptops, smartphones or tablets.