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English => News => Topic started by: Redaktion on July 10, 2020, 16:31:20

Title: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs compared to equivalent AMD Renoir APUs
Post by: Redaktion on July 10, 2020, 16:31:20
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
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: JayN on July 10, 2020, 16:53:53
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.   
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: Agfsfhxzafhx on July 10, 2020, 17:26:23
 We'll see when reviews come
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: john10072020 on July 10, 2020, 21:46:50
Userbench? You should ban that benchmark/site even if it does, sometimes, post interesting results.

UserBench...... If AMD then final_score = score*0.75
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: wow&wow on July 11, 2020, 02:08:55
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 :-)
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: AaR on July 11, 2020, 08:38:28
Intel CPUs have had dynamic frequency scaling for years now. Called SAGV. So I don't think you statement is true.
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: JayN on July 13, 2020, 00:39:29
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.
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: 10basetom on August 04, 2020, 06:00:29
If an AMD laptop supports 4266 MHz LPDDR4X, where can one actually buy one to upgrade their RAM?
Title: Re: Here is why LPDDR4x-4266 RAM seems considerably faster when coupled with Intel Tiger Lake-U CPUs
Post by: Adröit on August 10, 2020, 17:54:07
Quote from: 10basetom on August 04, 2020, 06:00:29
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.