Single Thread Efficiency Uplift Examined
Whereas some have taken the “better than 15% uplift in single-thread efficiency” as a sign of Zen 4 IPC enhancements, there are a variety of things at play right here. AMD doesn’t make any such IPC (directions per clock) declare, because the uplift is a mixture of the architectural enhancements (together with double the L2 cache per core), elevated clock speeds, and the transfer to higher-bandwidth DDR5 reminiscence.
Let’s have a look at the related footnote from AMD’s press launch, explaining below what situations the brand new Zen 4 pattern was in comparison with a Ryzen 9 5950X:
“Testing as of Might 5, 2022, by AMD Efficiency Labs. Single-thread efficiency evaluated with Cinebench R23 1T. AMD Ryzen 9 5950X System: ASUS ROG Crosshair VIII Hero X570, 2×8 DDR4-3600C16. AMD Ryzen 7000 Sequence: AMD Reference X670 Motherboard, 16-core Ryzen 7000 Sequence pre-production processor pattern, 2x16GB DDR5-6000CL30. All methods configured with Radeon RX 6950XT GPU (driver: 22.10 Prime), Home windows 11 Construct 22000.593, Samsung 980 Professional 1TB SSD, Asetek 280MM liquid cooler. Outcomes could range when last merchandise are launched in market.”
The 16-core Ryzen 7000 pre-production processor pattern was paired with 32GB (2 x 16GB) of DDR5 at 6000 MT/s, CL30. The Ryzen 9 5950X it was in comparison with had simply 16GB (2 x 8GB) of DDR4 at 3600 MT/s, CL16. Why they didn’t use 32 GB with the Ryzen 9 5950X is unknown, although in a single-threaded workload like Cinebench R23 I doubt it made any distinction. It nonetheless appears just a little odd, notably as AMD used such low latency DDR5 with the Zen 4 system (sure, CL30 at 6000 MT/s is definitely very low for DDR5), and CL16 DDR4, reasonably than CL14, within the Zen 3 system. Certain, the distinction would in all probability be negligible on this check, however I’m positive AMD has entry to 32GB of the lower-latency DDR4.
Yet one more factor: I’m not seeing 3D V-Cache talked about wherever, and AMD didn’t check the brand new 16-core Ryzen 7000 pre-production processor pattern’s single-thread efficiency in opposition to their latest Ryzen 7 5800X3D – as a substitute specializing in a comparability to the Ryzen 9 5950X. Now, at 5.5 GHz (and with DDR5-6000 CL30) the brand new CPU was going to win, regardless.
AMD at Computex 2022 Replay
You’ll be able to peruse AMD’s bulletins on their Computex web page (linked right here), and examine the YouTube video of AMD’s full occasion (embedded beneath):