The Register Takes AMD's Ryzen 9800X3D For A Spin

Review AMD is officially launching its hotly anticipated next-gen X3D desktop processors based on the Zen 5 architecture today, which means The Register can let you know about the 8-core Ryzen 9800X3D we've personally taken for a spin.

The X3D series comes specially packaged with an additional slice of L3 cache on top of the pre-existing L3 cache. The vertically stacked L3 cache that gives the series its X3D suffix initially launched in April 2022 with the Ryzen 7 5800X3D on AMD's Zen 3 microarchitecture. At the time, the cache-stacked processor made a splash in the mid-range desktop chip market, especially for gamers who couldn't afford flagship prices for the large pools of L3 that are required if you want to quickly retrieve game-related information.

We also saw X3D on the Zen 4 architecture in a variety of chips with different core and thread counts, including the 8-core Ryzen 7 7800X3D, which coincidentally also directly replaced the 5800X3D. In that case, the newer model didn't really feel like that much of an upgrade when it was squared up against the 5800X3D. It was better, but not by much in the way of overall performance and value.

Now the highly anticipated Zen 5 variant has finally arrived, with the same 8 cores and 16 threads we've seen before. The Ryzen 7 9800X3D features a combination of the latest Zen 5 cores with a hefty pool of 3D V-Cache – 96 MB in total to be exact. Meanwhile, we know AMD hasn't improved on the capacity as each 8-core X3D chip before it has the same 32 MB of L3 cache on the CCD with an additional 64 MB slice packaged via TSMC.

As AMD always claims with every X3D chip launch, and the 9800X3D is no different, the promise of the hardware for gamers is that it'll boost frame rates, reduce latency, and generally improve gameplay for those who have a fancy gaming monitor with a high refresh rate. While we've all seen the benefits of X3D in specific gaming titles that can use the gigantic pool of L3 cache, that's not the only area that a processor needs to deliver; gaming might be the area all the marketing is focused on, but the compute performance is also important.

Looking at the specs of the Ryzen 7 9800X3D, it's an 8-core chip with 16 threads, and comes with a base clock of 4.7 GHz, which boosts all the way up to 5.2 GHz, while running at a middle-of-the-road TDP of 120 W.

This launch is also AMD's first unlocked X3D processor, which finally gives those who love to tweak and overclock a reason to look toward X3D. While it's good that users can push it faster, chips these days are coming out of the factory already fast – which has killed quite a lot of the buzz from overclocking. Users can do it if they wish to, but it's not really needed.

What makes the X3D series stand out from the rest of AMD's Zen-based chips is the L3 cache. The 9800X3D stacks a total of 96 MB of L3 cache, with 64 MB of that from the 3D V-Cache packaging, which seems to be all AMD is giving X3D as we've seen this similar configuration in previous versions. The main difference this time is that AMD is using its second-generation 3D V-cache technology, with the 64 MB of SRAM (3D V-Cache) being packaged underneath and connected via TSVs and a direct copper-to-copper bonding process to the underneath of the CCD instead of on top as in previous generations.

AMD hasn't fully elaborated on why it has taken this route, but one reason could be that this setup eliminates any gaps and blank space between the SRAM and the CCD itself. Not only that, packaging it underneath also technically puts the 3D V-cache closer to the action, so to speak, and this could be a move to reduce the overall latency of the L3 cache. Also new are the Zen 5 cores, which brings with it the generational IPC improvements that come with AMD's latest microarchitecture.

Marketing claims are one thing, but real-world performance is another. Our focus here is to see how the Ryzen 7 9800X3D truly compares to its predecessor, the Ryzen 7 7800X3D, the chip it is effectively replacing in AMD's X3D push to dominate the PC gaming market. It's a pretty natural comparison to make, especially with both processors being built around an 8-core design with a single CCD – and of course, the 3D V-Cache. We'll also be looking closely to see if the 9800X3D can outperform the Ryzen 9 9900X, which has four more Zen 5 cores, but is just $20 cheaper in terms of MSRP.

Specs-wise, the Ryzen 7 9800X3D doesn't seem all that out of place in AMD's 9000 series lineup, but it's not a flagship in terms of core count. The 9950X and 9900X bring that muscle to the table with 16 and 12 cores, respectively, and as we know, the 9800X3D sticks with the same 8-core configuration as the 7800X3D it replaces. It's a deliberate trade-off from the other Ryzen 9000 chips as it has fewer cores, but more L3 cache, which is all aimed at squeezing out extra frames in CPU-bound gaming.

For testing, we'll be running the Ryzen 7 9800X3D at JEDEC-standard memory speeds, along with a few additional runs at DDR5-6000, which AMD suggests as the ideal performance setting. JEDEC speeds are what users get when they install the memory and go "plug and play" without any fancy boosts – essentially, this is how most people use their systems day-to-day. This setup also keeps things apples-to-apples with our existing data, allowing for a fair comparison across CPUs. It keeps the testing rigorous and cuts through any marketing fluff. Let's see what this chip really brings to the table.

We're running the Ryzen 7 9800X3D through benchmarks covering different workloads. Blender tests its multi-threaded rendering performance, while yCruncher pushes its compute and memory capabilities by calculating Pi. CineBench R23 and 2024 give us some single and multi-core performance comparisons, while a Dwarf Fortress simulation is also used to see how the Ryzen 7 9800X3D handles very complex single-threaded tasks.

Opening with power testing, we measure the peak power of each chip using yCruncher with AVX, which is very intensive. By doing this, it's easy to see how much power can be drawn from a CPU, even those generally meant to be restricted to some degree. As we can see from our testing of the Ryzen 7 9800X3D, it remained within its rated TDP of 120 W and didn't stray above, even when being hammered under AVX. Usually with Ryzen chips of late, there are two power variables to consider, TDP and PPT, or package power tracking, which is essentially what the AM5 socket can deliver to the CPU. As we can see, the Ryzen 7 9800X3D is at least adhering to TDP, while the PPT value can go anywhere up to 162 W.

Rendering benchmarks

In Blender 3.6, an open source 3D creation suite, rendering is the primary use, and it favors chips with higher core counts. The Ryzen 7 9800X3D doesn't do too badly here at around 22 percent; that's a good improvement. Still, it trails behind the bigger non 3D V-Cache Ryzen 9 9000 series chips. The flagship Ryzen 9 9900X is around 82 percent faster in the Pabellon test, and is also around 9 percent faster than the 7800X3D chip in the BMW_27 test, and a good chunk faster in the longer Pabellon scene – unsurprisingly, given it has double the cores and threads available to it.

Focusing on performance in CineBench R23 and the newer 2024 edition, the Ryzen 7 9800X3D is on average 15 percent faster in single-threaded performance over the Ryzen 7 7800X3D, and in both multi-thread CineBench tests is around 24 percent quicker on average. That's quite a good jump in performance between the two chips when you're going up only one generation.

Encoding and simulation

In our encoding and simulation tests, we're also seeing quite a nice uplift in performance over the previous Ryzen 7 7800X3D. The Ryzen 7 9800X3D is on average around 14 percent better than its predecessor, which is a nice double-digit bump to performance. Comparing the 9800X3D to the similarly priced yet more powerful Ryzen 9 9900X, on average it's better across these tests by around 18 percent, but it trails behind the 12-core chip in multi-threaded tests such as yCruncher – more cores make it faster to compute Pi than any bumps to L3 cache could.

Gaming @ 1080p

Now we come to gaming performance, which we've opted to run at 1080p high settings – which isn't a primarily GPU-bound resolution – so that we can see how the 9800X3D does compared to the previous 7800X3D and, of course, all those chips without the 3D V-cache. Across the three titles we elected to choose, the Ryzen 7 9800X3D does surprisingly well with an uplift on average of just under 7 percent compared to the 7800X3D. It's not as big of a bump compared to other areas such as rendering and simulation, but there's more at play in gaming than just the CPU; the GPU and memory also play a pivotal role in how well games perform.

Compared to the Ryzen 9 9900X, the 3D V-cache on the 9800X3D shows where its credentials lie, as AMD claims. The results on our small pool of games shows the 9800X3D is on average an impressive 18 percent faster when gaming at 1080p on our MSI GeForce RTX 4080 graphics card.

Of course, every game is different; some engines make better use of L3 cache and it's noticeable, and in others it makes absolutely no difference whatsoever. Unfortunately, despite crying out for one for the last two years, there's no dedicated list of specific games, at least not to our knowledge, that benefit from 3D V-Cache, which would allow users to make a more informed choice. Maybe one day AMD can get this done.

Let them eat cache

On paper, AMD's 3D V-cache-packed 8-core chip looks just like the other 800X3D chips we've seen, just with the latest Zen 5 cores, which bring their own uplifts and benefits. The point is that the Ryzen 7 9800X3D does a better job and feels more like how a generational replacement should be; going from Zen 4 to Zen 5 seems more like an improvement in terms of "overall" performance than when AMD went from Zen 3 (5800X3D) to Zen 4 (7800X3D).

In our testing, and being specific to just gaming here, the Ryzen 7 9800X3D is around 7 percent on average better than the 7800X3D – not earth-shattering, but still a clear improvement.

More impressively, though, it manages to outpace AMD's 12-core Ryzen 9 9900X by around 18 percent in our testing, showing that, in certain cases, more L3 cache can beat core count. That's not bad for a chip that sticks to a traditional 8-core configuration against the 12-core setup of its marginally pricier sibling. It's also a clear indicator that if the games are swayed by more cache than cores, L3 cache can make a big difference in CPU-bound titles. Frame rates go up, latency drops, and AMD's marketing around 3D V-Cache doesn't appear misplaced.

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Outside of gaming, however, the 9800X3D's story is bit more sticky. In benchmarks such as Blender and y-cruncher, which are heavy on multi-threading, we see a ceiling when there are just 8 cores. Of course, it's great that the 9800X3D is around 14 percent better on average across all our simulation and compute-focused tests, but put it against the Ryzen 9 9900X, which is just $20 more, and it's clear that where more cores can be utilized by the workload, the more it will pull ahead from the lower-core chip. Thus, the 9800X3D might not be your first pick if you're regularly rendering or encoding, but it is in compute where the Ryzen 9 9900X really shines, flexing its extra cores and threads and putting the 9800X3D squarely in its place when it comes to raw, multi-threaded compute.

Gamer's delight

All in all, the Ryzen 7 9800X3D is a decent performer but where it shines brightest is in gaming. At a pure grunt level compared to the other Ryzen 9000 series, especially the Ryzen 9900X, it can physically and logically compete with its bigger Zen 5 cousin in tasks that demand raw core count.

However, if compute performance is more of a requirement, it's not as good, so if you're after something that's a bit more of an all-rounder, the Ryzen 9 9900X might just be the better choice for that extra $20.

As when the Ryzen 7 7800XD replaced the Ryzen 7 5800X3D, the 9800X3D doesn't reinvent the wheel, but it doesn't really need to. It's a generation upgrade with the latest Zen 5 cores, which do bring an uplift in performance, but this time the replacement actually feels much like an upgrade as opposed to just opting for a newer chip for the sake of it.

For those who care about high-refresh-rate gaming and don't mind a few trade-offs elsewhere, such as slower compute or video rendering taking longer to complete, the Ryzen 7 9800X3D is a compelling option for gamers who are content with 1080p and want to boost those frames without paying flagship prices. ®