AMD Threadripper Pro Review: An Upgrade Over Regular Threadripper?

Since the launch of AMD’s Threadripper Pro platform, the desire to see what eight channels of memory brings to compute over the regular quad-channel Threadripper has been an intriguing prospect. Threadripper Pro is effectively a faster version of AMD’s EPYC, limited for single CPU workstation use, but also heralds a full 280 W TDP to match the frequencies of the standard Threadripper line. There is a 37% price premium from Threadripper to Threadripper Pro, which allows for ECC memory support, double the PCIe lanes, and double the memory bandwidth. In this review, we’re comparing every member of both platforms that is commercially available.

Threadripper Pro: Born of Need

When AMD embarked upon its journey with the new Ryzen portfolio, the delineation of where each product sat in the traditional market has not always been entirely clear. The first generation Ryzen was earmarked for standard consumers, however the top of the line Ryzen 7 1800X, with eight cores, competed against Intel’s high-end desktop market. The Zen 2-based portfolio saw the mainstream Ryzen go to 16 cores, pushing past Intel’s best 18-core HEDT processor at the time in most tests. That Zen 2-based Ryzen 9 3950X was still classified as a ‘mainstream platform’ processor, as it only had 24 PCIe lanes and dual-channel memory, sufficient for mainstream users but not enough for workstation markets. These mainstream processors were also limited to 105W TDP.

At the other end of the scale was AMD EPYC, with the first generation EPYC 7601 having 32 cores, and the second generation EPYC 7742 having 64 cores, up to 225W TDP. These share the same LGA4094 socket, have eight channels of memory, full ECC support, and 128 PCIe lanes (first PCIe 3.0, then PCIe 4.0), with dual-socket support. For workstation users interested in EPYC, AMD launched single socket ‘P’ versions. These offered the same features, at around 200 TDP, losing some performance to the regular non-P versions.

AMD then launched Threadripper, a high-end desktop version of EPYC that went all the way up to 280 W for peak frequency and performance. Threadripper sat above Ryzen with 64 PCIe lanes and quad channel memory, enabling mainstream users that wanted a bit more to get a bit more. However workstation users noted that while 280 W was great, it lacked official ECC memory support, and compared to EPYC, sometimes the reduced memory channel support and reduced PCIe compared to EPYC stopped Threadripper being adopted.

So enter Threadripper Pro, which sits between Threadripper and EPYC, and in this instance, very much more on the EPYC side. Threadripper Pro has almost all the features of AMD’s EPYC platform, but in a 280W thermal envelope. It has eight channels of memory support, all 128 PCIe 4.0 lanes, and can support ECC. The only downside to EPYC is that it can only be used in single socket systems, and the peak memory support is halved (from 4 TB to 2 TB). Threadripper Pro also comes at a small price premium as well.

One of the biggest pulls for Threadripper and Threadripper Pro has been any market that typically uses high-speed workstations and can scale their workloads. Speaking to a local OEM, the demand for Threadripper and Threadripper Pro from the visual effects industry has been off the charts, where these companies are ripping out their old infrastructure and replacing anew with AMD. This has also been spurned by the recent pandemic, where these studios want to keep the expensive hardware onsite and allow their artists to work from home via remote access.

Threadripper Pro CPUs: Four Models, Three at Retail

When TR Pro launched in 2020, the processors were a Lenovo exclusive for the P620 workstation. The deal between Lenovo and AMD was not disclosed, however it would appear that the exclusivity deal ran for six months, from September to February, with the processors being made retail available on March 2nd.

During that time, we were sampled one of these workstations for review, and it still remains one of the best modular systems I’ve ever tested:

Lenovo ThinkStation P620 Review: A Vehicle for Threadripper Pro

AMD’s first Threadripper Pro platform has four processors in it, ranging from 12 cores to 64 cores, mimicking their equivalents in Threadripper 3000 and EPYC 77x2 but at 280W.

Sitting at the top is the 64-core Threadripper Pro 3995WX, with a 2.7 GHz base frequency and a 4.2 GHz turbo frequency. This processor is the only one in the family to have all 256 MB of L3 cache, as it has all eight chiplets fully active. The $5490 price is a full 37.5% increase over the Threadripper 3990X at $3990.

Middle of the line is the 32-core Threadripper Pro 3975WX, with a 3.5 GHz base frequency and a 4.2 GHz turbo frequency. AMD decided to make this processor use four chiplets with all eight cores on each chiplet, leading to 128 MB of L3 cache total. At $2750, it is also 37.5% more expensive than the equivalent 32-core Threadripper 3970X.

The following two processors have no Threadripper equivalents, but also represent a slightly different scenario that we’ll explore in this review. Both the 3955WX and 3945WX, despite being part of the big Threadripper Pro family, only use two chiplets in their design: 8 core per chipet for the 3955 WX and 6 core per chiplet for the 3945WX. This means these processors only have 64 MB of L3 cache, making them somewhat identical to the Ryzen 9 3950X and Ryzen 9 3900X, except the IO die means there is eight channels of memory and 128 PCIe lanes here.

The 3955WX has a higher base frequency, but the 3950X has the higher turbo frequency. The 3950X is also cheaper, and motherboards are cheaper! It might be worth partitioning these out into a separate comparison review.

The final Threadripper Pro processor, the 3945WX, does not have a price, because AMD is not making it available at retail. This part is for selected OEM customers only it seems; perhaps the limited substrate resources in the market right now makes it unappealing to make too many of these? Hard to say.

Motherboards: Beware!

Despite being based on the same LGA4094 socket as both Threadripper and EPYC, Threadripper Pro has its own unique WRX80 platform that has to be used instead. Only select vendors seem to have access/licenses to make WRX80 motherboards, and your main options are:

• ASUS Pro WS WRX80E-SAGE SE WiFi ($1000)
• Supermicro M12SWA-TF (~$750)
• GIGABYTE WRX80 SU8-IPMI ($790)

All three boards use a transposed LGA4094 socket, eight DDR4 memory slots, and 6-7 PCIe 4.0 slots.

Though beware! There is an option of finding an old/refurbished Lenovo P620 motherboard. It is worth noting that Lenovo is exercising an AMD feature for OEMs: processors used in that Lenovo motherboard will be locked to Lenovo forever. This is part of AMD’s guaranteed supply chain process, allowing OEMs to hard lock processors into certain vendors for supply chain end-to-end security that is requested by specific customers. In that instance, if you might ever want to break down your system to upgrade and sell off parts, it is not recommended you find a Lenovo TR Pro system unless you buy/sell it as a whole.

This Review

The main goal of this review is to test all of the Threadripper Pro 3000 hardware and compare against the equivalent Threadripper 3000 to get a sense of how much performance is gained by the increased memory bandwidth, or lost due to the slight core frequency differences. We are also including Intel’s best HEDT/workstation processor for comparison, the W-3175X, as well as the top consumer-grade processors on the market. All systems are tested at JEDEC specifications.

Many thanks to Kingston for supplying a full set of KSM32RD8/16MEI - 16x16 GB of DDR4-3200 ECC RDIMMs for enterprise testing in systems like Threadripper Pro.

As part of this review, we are also showcasing the 64 core processors in 128T mode as well as 64T mode. This is being done to showcase how some processors can get better performance by having better memory bandwidth per thread - one of the issues with these high core count processors is the limited amount of memory bandwidth each thread can access. Also, some operating systems (such as Windows) struggle above 64 threads due to the use of thread groups.