AMD Zen 4 Ryzen 9 7950X and Ryzen 5 7600X in the test: Reconquering high-end

While AMD’stogether we advance_PCsAt the event in late August, the company unveiled its Ryzen 7000 series of desktop processors with four SKUs targeting the mid-range and high-end segments of the market. After whetting the audience’s appetite with this announcement, AMD will officially release its long-awaited next-gen CPUs tomorrow.

The launch of the Ryzen 7000 series brings with it a lot to digest for both casual fans and hardcore hardware enthusiasts alike. For its latest line of chips, AMD has updated its desktop CPU platform from the top down, releasing not just new CPUs, but a whole new platform, the Socket AM5 around it. As a result, these chips are not drop-in compatible with existing AMD motherboards for the first time in several generations. But at the same time, it has allowed AMD to deliver a number of platform improvements ranging from DDR5 and PCIe 5.0 support to improved power management features. AMD has even managed to sneak an entry-level iGPU based on the Radeon RDNA2 architecture into the chip.

The Ryzen 9 7950X: 16 cores, 32 threads, new 170W TDP: $699

As always, we’ll start with the CPUs themselves. AMD’s flagship product for this generation is the Ryzen 9 7950X, a 16-Zen 4-core CPU that has AMD topping the charts for both single-threaded and multi-threaded workloads would like. The Ryzen 9 7950X has a base frequency of 4.5 GHz and a peak turbo clock speed of 5.7 GHz, making it the highest clocked desktop x86 CPU to date.

But don’t think that AMD’s Zen 4 architecture is all about clock speeds. AMD has also improved the IPC of its CPU architecture by an average of 13% – mainly based on the addition of AVX-512 instruction support and conveniently larger caches and buffers throughout the CPU – meaning the Ryzen 7000 chips are delivering significant performance can make improvements in a variety of single-threaded workloads.

As for multi-threaded workloads, AMD has been able to improve performance there too, albeit relying on both architectural improvements and higher TDPs to enable higher sustained clock speeds. One of the enabling factors here is that the AM5 platform allows for higher chip TDPs – up to 170W in the case of the 7950X – which is about 65W higher than the maximum TDPs on AMD’s fastest 16-core Ryzen 5000 parts. As a result, AMD is well-positioned to deliver the “leadership”-class performance it aspires to, but not entirely for free.

Ryzen 9 7900X, Ryzen 7 7700X and Ryzen 5 7600X

The Ryzen 9 7900X, which is a 12C/24T and 170W TDP part, moves down a notch. It has a higher base frequency than the 7950X of 4.7GHz but with a slightly lower boost frequency of up to 5.6GHz.

Underneath that, AMD has launched a Ryzen 7 part designed for mid-range desktop computing, the Ryzen 7 7700X. This is an 8C/16T SKU with a single core boost frequency of up to 5.4GHz and a base frequency of 4.5GHz. Notably, this part has a more AMD-typical TDP of 105W, unlike the Ryzen 9 parts.

Finally, we have the Ryzen 5 7600X, which is also aimed at the mid-range market and is the cheapest member of AMD’s new stack. With 6C/12T and a TDP of 105W, the 7600X is Zen 4 at a cheaper price. The chip runs at a base frequency of 4.7GHz, with a modest (compared to Ryzen 9) boost frequency on a single core of 5.3GHz.

If you compare apples to apples, so to speak, between the parts of the new Ryzen 7000 series and the parts of the previous generation Ryzen 5000 series, Ryzen 7000 has made some big overall improvements to the chips’ capabilities. All Ryzen 7000 chips offer significant increases in both base and boost frequencies, which bodes well for overall performance. The worst we can say is that AMD hasn’t increased core counts in any price point/market segment, so any performance gains we’ll see here today are purely from architecture and clock speeds and not from the more immediate MT throw gain of more silicon on the thing.

AMD’s performance gains have been made possible in part by the superior power efficiency of the Zen 4 architecture. While the Zen 4 architecture is a modest refinement of Zen 3 and delivers a 13% IPC improvement, it also has the major benefit of being produced on TSMC’s 5nm process node, a complete node loss from TSMC -7nm process used for Ryzen 5000/3000. This efficiency has allowed AMD to increase clock speeds without damaging the power bank, with the 105W TDP 7700X seeing a 700MHz improvement with no change in TDP. And multi-threaded performance isn’t let down either; By increasing the upper TDP to 170W, AMD is able to keep the CPU cores on their 12C and 16C parts at higher sustained turbo clocks and deliver much better performance there too.

Of course, one of the main arguments here is that more performance demands more cooling, which is very true of the Ryzen 7000 series. The Ryzen 7000’s TjMax for its Precision Boost Overdrive technology is 95°C, which means the CPU uses all available thermal headroom up to that point to maximize performance.

Although this can be overridden with manual overclocking, the top-end Ryzen 7000 chips still require better cooling than their Ryzen 5000 counterparts. Users will have to employ higher quality and more aggressive coolers to squeeze every last drop of performance out of the Zen 4, as most of us are used to. AMD, for its part, has taken all of this into account with its design choices and product marketing, clearly recommending Ryzen 9 79×0 owners to use a liquid cooler with these chips. However, this means that AMD doesn’t bundle its own CPU coolers with its retail SKUs, instead directing buyers to fairly powerful third-party coolers.

New AM5 socket: AM4 coolers also support AM5

AMD has also switched to a new platform for Ryzen 7000 called AM5. Along with AM5 also comes a new socket, the titular socket AM5, an LGA 1718 socket that is AMD’s first use of the LGA form factor for mainstream desktop CPUs. What’s interesting now is that AMD has stated that most AM4 coolers will support the new AM5 socket, which is great for maintaining compatibility with existing coolers.

It also means that AM4 is slowly on its way to becoming a thing of the past. While AMD is still (many) months away from replacing its entire Ryzen 4000/5000 stack with Ryzen 7000 parts, today is day one and the first step in that direction. Nonetheless, AM4 currently has some incredible deals (e.g. 5800X3D) as well as support for cheaper DDR4 memory. This is in contrast to the AM5 platform, which is designed exclusively for DDR5. However, when it comes to memory, AMD has a slight advantage over Intel; While Intel’s 12th Gen Core chips only support a maximum (JEDEC) speed of DDR5-4800, the Ryzen 7000 chips are officially designed for DDR5-5200.

Matching the new AM5 platform and the provision of motherboards for their new CPUs, AMD has introduced four (almost) new chipsets. These are the B650 and X670, as well as their “Extreme” variants, the B650E and X670E. The top-end X670E series will offer both PCIe 5.0 lanes to the top PEG slot and support for PCIe 5.0 NVMe storage devices. The regular X670 chipset, on the other hand, foregoes the mandatory PCIe 5.0 speeds for the PEG slot in favor of the easier-to-implement PCIe 4.0. In any case, both versions of the X670 are said to offer a wealth of I/O options, and in keeping with the general tiered structure of AMD’s AM5 chipsets, X670 boards generally offer better designs, better controllers, and better specs.

The B650 chipsets, on the other hand, are more affordable because they eliminate some of the I/O lanes and overall I/O flexibility of the X670 chipsets. Like the Extreme X670, the B650E is intended for boards that offer PCIe 5.0 for the PEG slot and NVMe storage. Otherwise, the lowest B650 chipset chooses PCIe 4.0 again for the PEG slot too.

Only the X670/X670E boards are available at launch this week. Buyers looking for the cheaper B650/B650E boards will have to wait until October.

New I/O die: TSMC 6nm for Ryzen 7000

As with the last few Ryzen desktop generations, AMD builds its CPUs from chiplets for the Ryzen 7000 series. All Ryzen 7000 desktop chips consist of an I/O die (IOD) and one or two core complex dies (CCDs), depending on the SKU. The IOD houses all PCIe 5.0 lanes, the integrated DDR5 memory controller (IMC) and new for Ryzen 7000 an integrated GPU based on AMD’s Radeon RDNA2 GPU architecture. All in all, the IOD used for the Ryzen 7000 is a fairly significant overhaul compared to AMD’s previous IOD, with AMD implementing several new performance and power savings features and further reducing power consumption thanks to TSMC’s 6nm process.

It’s time to dive deep into all of AMD’s new improvements and changes for its Zen 4 microarchitecture. On the following pages we will go into the following:

1. Ryzen 7000 Overview: Comparison of Ryzen 7000 vs. Ryzen 5000 specs
2. Socket AM5: The new platform for consumer AMD
3. More I/O for AM5: PCIe 5, additional PCIe lanes and more displays
4. AM5 chipsets: X670 and B650 built by ASMedia
5. DDR5 & AMD EXPO memory: Memory overclocking AMD’s way
6. Ryzen 7000 I/O Die: Finally TSMC & integrated graphics
7. Zen 4 architecture: energy efficiency, performance and new instructions
8. Zen 4 execution pipeline: Familiar pipes with more caching
9. test stand and construction
10. Core-to-Core Latency
11. SPEC2017 single-threaded results
12. SPEC2017 multithreaded results
13. CPU Benchmark Performance: Performance, Web and Science
14. CPU benchmark performance: simulation and coding
15. CPU benchmark performance: rendering
16. CPU Benchmark Performance: Legacy Tests
17. Gaming Performance: 720p and below
18. Gaming performance: 1080p
19. Gaming performance: 4K
20. Conclusion