AMD might be about to give dual-socket functionality to their Threadripper CPUs


In a nutshell: At the end of last week, an AMD report describing the features and specifications of the upcoming 5000-series Threadripper Pro CPUs was leaked. It said that all five models would have dual-socket functionality. Shortly after, two Threadrippers appeared in the PassMark database having completed the benchmark in dual-socket mode – but they’re not from the 5000-series.

Instead, they were two of the seventeen-month-old flagship of the 3000-series: the 3995WX. In theory, because the CPU shares its hardware with the dual-socket-capable Epyc 77×2-series, the 3995WX has only ever been prevented from engaging in a dual-socket mode by software limitations.

Working in tandem, the two CPUs achieved a score of 123,631 points; 35% more than the median result of a single 3995WX, and the highest score of any two-CPU pairing in the database.

If the result is genuine, which it seems to be, then there’s only one likely culprit: AMD themselves. It’s simply too unlikely that another party could modify the two CPUs, which cost some $8,800 each, and the requisite motherboard, successfully.

As for why AMD would be experimenting with their old CPUs, our best guess is that the creation of the first dual-socket sWRX8 motherboards for the 5000-series has raised some questions about their backward compatibility. A microcode update could conceivably enable dual-socket functionality in 3000-series CPUs, though AMD doesn’t have much of an incentive to create one.

2021 12 26 image

Credit: Onur Binay

At a minimum, though, AMD does have an incentive to enable dual-socket functionality on the 5000-series. In the past, doing so would’ve cannibalized the Epyc series; it’s one of the main features that differentiate the two product lines. But, as of 2022, the Epyc series will be an entire “generation” ahead of Threadripper and use a newer architecture at a minimum, if not a newer node as well.

Most of the available information about the 5000-series comes from the aforementioned report, which was acquired by Igor’s Lab. Its contents haven’t been verified beyond a few match-ups with other leaks, but Igor’s Lab is a trustworthy source. That said, sometimes specifications are changed in the lead-up to the processors’ announcement.

Possible Threadripper Pro 5000-series Specifications

5995WX 5975WX 5965WX 5955WX 5945WX
Cores / Threads 64 / 128 32 / 64 24 / 48 16 / 32 12 / 24
Single-Core Boost Clock 4.55 GHz
All-Core Boost Clock 2.70 GHz 3.60 GHz 3.80 GHz 4.00 GHz 4.10 GHz
Base Clock 2.25 GHz 2.70 GHz 2.80 GHz 2.90 GHz 2.94 GHz
L3 Cache 256 MB 128 MB 64 MB
L2 Cache 32 KB 16 KB 12 KB 8 KB 6 KB
TDP at Boost Clock 280 W
TDP at Base Clock 229 W 190 W 171 W 152 W 138 W

There’s now only Pro (with a “W”) versions of the processors, according to Igor’s Lab. This year, there are five, up from four; the addition was of the 24-core model.

On the whole, the specifications of these processors aren’t too different from their predecessors. Their all-core clock speeds are a couple of hundred megahertz higher or lower in some cases, but broadly similar. Only their single-core clock speed is a consistent upgrade of 250-350 MHz.

Like the Ryzen 5000-series, the biggest upgrade is under the hood: the Zen 3 architecture. In our testing, it could provide an IPC performance uplift of 10-20% in various applications. It might provide an even larger uplift on higher-core count models that benefit from its impressive inter-core and cache latency, vastly improved over the Zen 2 architecture of the 3000-series.

But it’s more likely to be the dual-socket functionality driving the sales, should it eventuate. It would be interesting to see what 128 unlocked cores can do.



Source link

Leave a Comment