[Update 10/11/2022] Afterthoughts on Zen 4 Reviews, and How to Make Sense of Them All
The new Zen 4 CPUs don't make sense, here's why.
Today is the day that AMD lifts the embargo on the upcoming AM5 socket Zen 4 CPUs. Based on all the reviews I have read/watched, I will try to make sense of them all, and point out a few very important, but rarely brought up detail.
The New Platform, At What Cost?
First, let’s look at how the most affordable Zen 4 CPU, which is the Ryzen 5 7600X, compares to a similar priced AM4 (Zen 3) or LGA 1700 (Intel 12th Gen) CPUs. From what I see, the Ryzen 5 7600X delivers, on average, about 20% more performance than the Ryzen 5 5600X in 1080p gaming. Thus, for an apples-to-apples comparison, if the total cost of AM5 platform upgrade is within 20% more expensive than what a AM4 platform costs, then this could be viewed as an upgrade in both performance and value.
However, that’s not the case. Let’s take a look at the following example builds where I only factor in CPU + MB + RAM costs, since they are Required to upgrade to AM5.
|CPU||Ryzen 5 5600X - $215||Ryzen 5 7600X - $299|
|MB||MSI X570-A PRO - $150||MSI Pro X670-P WiFi - $290|
|RAM||Corsair Vengeance RGB 32GB 3600C16 - $98||G.SKILL Trident ZS 32GB 6000C40 - $205|
As you can see, the spec’d AM5 platform is 71.4% more expensive than the AM4 platform. Unfortunately, there are few benchmarks where the Ryzen 5 7600X leads its predecessor by 71.4%, making the value of the AM5 platform incredibly poor.
Also, I left out a very important component, which is cooling. Zen 4 CPUs will boost to a temperature limit of 95C, which means the better the cooling, the more performance can be extracted from the CPU you’ve bought, though this phenomenon is more manageable on the Ryzen 5 7600X. I’d still suggest something like a Noctua D15 for air cooling, or a quality 280mm AIO for liquid cooling. That will set you back for another $100 at least, whereas the Ryzen 5 5600X can be paired with its boxed Wraith Stealth cooler.
Let’s take on this value problem from another perspective: How do we make Zen 4 even remotely relevant for an upgrade?
Continuing from the chart above, if we assume an overall 30% performance uplift by upgrading to Zen 4, which is quite generous already, we can derive the platform cost of the Zen 4 has to be somewhere around $463 x 1.3 = $602 to even consider this is an upgrade. Furthermore, if we subtract the CPU cost from the total, we’d be left with $303 for our motherboard and RAM, which is impossible to achieve at the moment, unless the upcoming B650 will be significantly cheaper than the X670 offerings, and DDR5 would come down in price when B650 launches. Since we are “upgrading”, we will use the old cooler so we don’t have to paid extra for another one.
With that said, if we are to spend any more than this $303 budget, this “upgrade” won’t actually bring us any added benefit for a gaming PC build. Mind you, we are talking about almost a Radeon 6700XT ($350 at the moment) of a price gap here. For gamers, there’s nothing that the Zen 4 Ryzen 5 7600X can run 1080p/1440p at 60 FPS that won’t run on Zen 3 Ryzen 5 5600X.
So what will this upgrade bring? First and foremost, is PCIe 5.0 connectivity. But there’s no PCIe 5.0 GPU available, and the upcoming NVIDIA 40 series are still on PCIe 4.0. Maybe we would like to have a PCIe 5.0 SSD, but that won’t do us any good than the already blazing-fast PCIe 4.0 SSD, since game loading is largely dependent on random R/W, instead of the marketed sequential R/W for most SSDs.
[UPDATE 10/03/2022] Micro Center was running a special where you can purchase a Zen 4 Ryzen 7/9 CPU at MSRP and get a free G.Skill 32GB DDR5 5600 RAM kit. This softens the blow tremendously and I quickly jumped on it by getting a Ryzen 7 7700X for $399. So, if the Ryzen 7 7700X system is 50% faster than the Ryzen 5 5600X system in terms of CPU performance, then our projected system cost should be right around $700. Subtract the CPU+RAM for $399 from it, we are left with about $300 for a new motherboard and cooler. When B650 motherboards come out, I'd expect this to be very doable.
[UPDATE 10/11/2022] The lowest priced AMD B650 Motherboard seems to be the ASRock B650M PG RIPTIDE. It is currently on Newegg for "just" $169.99. It has one PCIe 4.0 x16 for the graphics card, one PCIe 4.0 x4 in the form of x16 from the chipset, and two PCIe 3.0x1 slots for other expansion card needs. On the storage side, it has two NVMe slots, one of which being PCIe 5.0x4, and the other is PCIe 4.0x4, alongside with four SATA 6Gbps ports. Honestly, this board should be $130 max given the specs. It is most comparable to Asus Prime B660M that I used for my NAS build. However, I like how Zen 4 CPUs added AVX-512 support while Intel most likely will still wall-off its AVX-512 from its P-cores, so I snatched this as my "entry-level" AM5 platform build, paired with the 7700X special deal I got from Micro Center.
I want to like the new AM5 platform, I really do. Something like the AVX-512 instruction set can greatly improve emulator performance, which I spend a lot of time playing. Frankly speaking, with the new DDR5 and architecture, a 30% improvement is nothing to be shamed at. However, the cost of this new platform is just so absurdly high at the moment, while providing minimal benefit that I can reap from day-to-day usage and gameplay, and certainly doesn’t make sense for me, or anyone intents to build a rig that’s gaming focused.
I would reiterate my point from my previous blog post here: