Zen 4 efficiency at 65W

In the third quarter of last year, AMD released the first CPUs based on the long-awaited Zen 4 architecture. Not only did they raise their Ryzen 7000 parts in terms of performance over the previous Ryzen 5000 series, but it also gave birth to AMD’s newest platform, the AM5. Some of the biggest advantages of Zen 4 and the AM5 platform include PCIe 5.0 support, DDR5 memory, and access to the latest and greatest in controller families.

While competition at the higher end of the x86 processor market is a metaphorical gun battle, AMD has struggled to offer users on tight budgets anything to plunge into. Zen 4 is clearly a powerful and highly efficient architecture, but with the added cost of DDR5, finding all the components that fit within tight budget constraints with AM5 isn’t as easy as it was with AM4.

AMD has launched three new processors designed to give budget users something to get their money’s worth, with performance that makes them suitable for users looking for Zen 4 hardware but without the huge financial outlay. The AMD Ryzen 9 7900, Ryzen 7 7700, and Ryzen 5 7600 processors all feature Zen 4 microarchitecture and come with a TDP of just 65W, making them viable for all types of users, such as enthusiasts looking for a more affordable entry point on the AM5 platform.

Of particular interest is AMD’s new entry-level offering for the Ryzen 7000 series: the Ryzen 5 7600, which offers six cores/twelve threads for entry-level enthusiasts looking to build a system with all the features of the AM5 and Ryzen 7000 family, but at a much lower price. We’re looking at all three of AMD’s new Ryzen 7000 65 W TDP processors to see how they fare against the competition, to see if AMD’s lower-powered, lower-priced non-X variants can offer anything in the way of value for consumers. We also aimed to see if AMD’s 65 W TDP implementation could shine on TSMC’s 5nm node process with performance-per-watt that AMD claims is the best on the market.

Over the past year, since AMD unveiled its Zen 4 core, we’ve posted several inches of the bar on microarchitecture, Ryzen 7000 processors, and the AM5 platform. Here is a list of our detailed Raphael (Zen 4) and Ryzen 7000 coverage:

Ryzen 9 7900, Ryzen 7 7700, Ryzen 5 7600, 65 W TDP from $229

Focusing on the latest 65-watt Ryzen 7000 processors, AMD is looking to offer better value across its series as well as various price drops on its X-class Zen 4 chips across the board. The new Ryzen 7000 non-X chips are available across multiple configurations and price points, some of which show better power efficiency than previous generations of their processors and the decision to revert to bundling the right coolers for greater value.

Unlike AMD’s X Series SKUs, which require efficient cooling due to their higher power consumption and higher thermal stress on the IHS, the new 65W models are designed with efficiency and performance per watt in mind. All aimed at making them (more) viable options for all kinds of system builders. To account for the lower TDP compared to the X Series SKUs, AMD has lowered its clock speed predictions for these new SKUs. Boost hours are still fairly high, which reflects what silicon can do for light workloads; But the official core clock speeds have been lowered further in order to keep the chips’ power usage under control in highly multi-threaded scenarios.

Starting with AMD’s highest 65W SKU, the Ryzen 9 7900 has 12 Zen 4 cores with a maximum boost speed of up to 5.4GHz. Additionally, it shares the same 64MB L3 cache as the Ryzen 9 7950X and Ryzen 9 7900X, but with a TDP more than 100W lower than the flagship model. The Ryzen 9 7900 is designed for content creators, gamers, and enthusiasts looking for a more affordable option.

Comparing the Ryzen 9 7900 directly to the Ryzen 9 7900X, the 65 W variant has a base clock speed of 3.6GHz, which is about a 23% decrease compared to its X-series sibling. Boost clock speeds, on the other hand, are more similar, with a boost frequency of 5.4GHz. on the Ryzen 9 7900, which makes things more palatable for enthusiasts.

AMD Ryzen 9 7900 12-cores/24-threads in CPU-Z

The 61% drop in TDP between the Ryzen 9 7900 (65 W) and the Ryzen 9 7900X (170 W) might raise some questions about raw performance yield. Certainly, the 7900 will see lower performance on significantly multi-threaded workloads; You still need a lot of power to light up a dozen Zen 4 cores at 5GHz+. What’s the upside to this, though? Having a lower TDP makes it more applicable in systems with limited space. Not only that, but it also means it’s easier to cool and shave off some of the budget needed to buy a high-end cooler, which could be spent on faster DDR5 memory, storage, or discrete graphics.

Moving up the stack to the Ryzen 7 series, the Ryzen 7 7700 has the same number of cores and threads as the current Ryzen 7 7700X, but with a 100MHz bump to boost clock speeds. Meanwhile, there is a base frequency of 3.6GHz, which is a decrease in the initial frequency of 900MHz. Other features include 40MB total cache, 32MB of L3 cache, and 8MB of L2 cache.

Overall, the Ryzen 7 7700 sees a 40W drop in TDP versus the 105 TDP of its X-series counterpart, which is noticeably smaller than the drop in the 7900 parts. So Zen 4 hardware isn’t being asked to give up a great deal of headroom here.

Slide from AMD’s Ryzen 7000 65 W chipset platform: Performance per watt is the focus

Another SKU from AMD’s Ryzen 7000 65 W offering is the Ryzen 5 7600. The Ryzen 5 7600 is an entry-level model of AMD’s latest high-performance AM5 platform, with six cores and a maximum boost clock speed of 5.1GHz. It shares many characteristics of the Ryzen 5 7600X, including 32MB of L3 cache with 6MB of L2 cache; That’s 1MB per core, which is an advantage for Zen 4 over 512KB of L2 cache per core over Zen 3. Another plus is the price, which the Ryzen 5 7600 is very attractive, with an entry-level price of $229, down from $299. US MSRP (and street price $269) for the 7600X. This gives users looking to opt for Zen 4 and TSMC 5 nm processor a more affordable option to consider opting for.

Like the rest of the Ryzen 7000 family, all three of the new 65W SKUs also include an integrated GPU made from two CUs built on RDNA2, in order to provide the most basic levels of integrated graphics. While more than satisfactory for simple desktop needs, they should not be confused with having the same levels of graphical power as the Ryzen series of APUs.

Finally, it’s also worth reminding everyone that, as has been the case for several generations of processors now, TDP is not the maximum power consumption value for either AMD or Intel – nor is the definition of TDP identical even between the two. For AMD, the metric to monitor is Package Power Tracking (PPT), which is the power level that the CPU socket allows the CPU to graph in terms of power. On the AM5 platform, AMD defines PPT as 1.35x TDP – so in the case of current 65W Ryzen processors, that means an 88W socket power limit.

Test bed and setup

In accordance with our processor testing policy, we take a suitable premium-class motherboard for the socket and provide the system with an appropriate amount of memory operating at the maximum frequency supported by the manufacturer. This is also normally run in sub-JEDEC times where possible. It should be noted that some users do not care about this policy, noting that sometimes the maximum supported frequency is relatively low, faster memory is available at a similar price, or JEDEC speeds can be prohibitive for performance.

While this comment makes sense, very few users implement memory profiles (either XMP or other) because they require interaction with the BIOS. Most users will return to the speeds supported by JEDEC – this includes both home and industrial users who may want to cut a cent or two off the cost or stay within the margins set by the manufacturer. Where possible, we will extend testing to faster memory modules either at the same time as the review or at a later date.

Current CPU test suite

For the AMD Ryzen 9 7900, Ryzen 7 7700, and Ryzen 5 7600 tests, we use the following test system:

Our updated 2023 CPU portfolio includes several benchmarks, tests, and workloads designed to show the variance in performance between different processors and architectures. These include UL’s latest Procyon suite with both desktop and image editing workloads simulated to measure performance on these tasks, and CineBench R23, Dwarf Fortress, Blender 3.3 and C-Ray 1.1.

Meanwhile, we’ve also implemented some older (but still relevant/illuminating) benchmarks from our 2021 CPU lineup. This includes benchmarks such as Dwarf Fortress, Factorio, and Dr. Ian Cutress’s 3DPMv2 benchmark.

We’ve also updated our game portfolio going forward to 2023 and beyond, including the latest racing game F1 2022, RTS Total War: Warhammer 3, and the popular Hitman 3.