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

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

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.

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.

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.