AMD Ryzen 7 3800X Review

AMD Ryzen 7 3800X Review

There are currently two options if you want an 8-core CPU based on AMD’s 7nm Zen 2 architecture. The Ryzen 7 3700X (see Issue 192, p16) is a beast, especially once overclocked, while the Ryzen 7 3800X we’re reviewing here has higher all-core boost and peak boost clocks at stock speed, as well as a higher TDP.

Whether it’s worth the extra cash is another matter, though, as the Ryzen 7 3700X is £50 cheaper, but sports a largely identical set of features.

As both CPUs have eight cores and 16 threads courtesy of Simultaneous Multithreading (SMT), let’s start with the frequencies, which are the main areas to consider.

The Ryzen 7 3800X has a base frequency of 3.9GHz, which is 300MHz higher than that of the Ryzen 7 3700X. It also has a 100MHz boost advantage at 4.5GHz.

While the Ryzen 7 3700X’s all-core boost isn’t officially listed by AMD, it sat at 4GHz in our water-cooled test system, and the Ryzen 7 3800X has a sizeable advantage here too, with our sample hitting 4.2GHz under load.

Those higher frequencies have an impact on thermals and power though. The Ryzen 7 3700X has a TDP of just 65W, but the 3800X sits at 105W. Both CPUs include the same Wraith Prism RGB cooler despite that TDP difference, however.

The cache sizes are also identical, with both chips having 512KB of L2 cache per core (for a total of 4MB).

Comparatively, AMD’s two 6-core 3rd-gen Ryzen CPUs, the Ryzen 5 3600 and 3600X, have two fewer cores so they have 1MB less L2 cache than the 8-core CPUs.

All four of the above CPUs have 32MB of L3 cache, and are made up of two quad-core Core Complexes, with two cores disabled on the 6-core chips.

In terms of the competition, the Ryzen 7 3800X is around £40 more expensive than Intel’s Core i7-9700K thanks to Intel’s recent price cuts, but it still remains far cheaper than the blue team’s flagship mainstream CPU, the Core i9-9900K.

The latter will set you back another £60 or so over the price of the 3800X, but it too has seen a price fall, so it now leaves you with plenty of change from 500 dollars.

AMD Ryzen 7 3800X Review

Performance

It’s clear from the limited availability of the Ryzen 9 3900X, and the delay to the Ryzen 9 3950X, that there’s a high degree of speed-binning going on with AMD’s 3rd-gen Ryzen CPUs and we were hopeful that our Ryzen 7 3800X, being in the upper echelons, might reach a higher overclock than the 3900X, especially as it has fewer cores.

We weren’t disappointed, with our 3800X sample reaching 4.4GHz across all cores using our maximum vcore of 1.425V – you may be able to drop the latter a bit for a more long-term overclock as well.

This means that, unlike many other recent AMD CPUs, an all-core overclock only loses you 100MHz compared to the peak boost of 4.5GHz.

As such, it’s definitely worth manually overclocking the Ryzen 7 3800X for heavily multi-threaded workloads, and you won’t lose much lightly threaded performance compared with running at stock speed either.

This overclock only saw the load power consumption rise from 215W to 233W, and the chip was easily tameable by our 240mm all-in-one liquid cooler.

By comparison, both of Intel’s 8-core CPUs drew a similar amount power at stock speed and significantly more when overclocked, although admittedly hitting much higher frequencies.

In our RealBench image editing test, the Ryzen 7 3800X actually managed to outstrip the Ryzen 9 3900X, albeit within the margin of error we generally expect for this test, and it wasn’t that much faster than the other 3rd-gen Ryzen CPUs we’ve tested.

However, it definitely had the measure of the two 8-core Intel CPUs. Our heavily multi-threaded video encoding test painted a clearer picture, with the Ryzen 7 3800X outstripping the Core i7-9700K by more than the price difference suggests, with a score of 610,355 compared to just 498,461.

Similarly, despite costing another £60 or so, the Core i9-9900K was only a small amount faster. The system score of 241, 240 is only just short of the Core i9-9900K and not a whole lot more than the Ryzen 7 3700X. But the Ryzen 9 3900X does offer a fair amount more grunt here, easily topping 300,000.

Once it was overclocked on all cores, the 3800X’s system score rose to 253,121. With the biggest gain being seen in the video encoding test. But it was slower in the image editing test, due to our all-core overclock being slower than the single-core stock speed boost frequency.

Overclocking also offered sizeable increases to the Far Cry 5 benchmark, with the minimum frame rate rising from 91fps to 97fps.

Even so, this test is an area where Intel still reigns supreme, although bear in mind that not all games respond so strongly to using different CPUs, and that this is a deliberately CPU-limited test.

AMD RYZEN7 3800X Results

GIMP Image Editing

GIMP IMAGE EDITING

Handbrake H.264 Video Encoding

Heavy Multi Tasking

Total System Power Consumption

System Core

Cinebench R20 Single Threaded

Cinebench R20 Multi Threaded

FAR CRY 5 (1,920 x 1,080, Ultra settings)

Conclusion

Compared with Intel’s offerings, the Ryzen 7 3800X is a beast, usually matching or bettering the Core i9-9900K in multi-threaded benchmarks and trouncing the Core i7-9700K.

The latter, though, can be bought for less than £350. So it’s definitely worth considering if gaming is your top priority.

However, you won’t see benefits in all games, and as soon as you dip into multi-threaded workloads, the Ryzen 7 3800X completely outstrips both Intel CPUs in terms of value and very often in raw performance too.

The Ryzen 7 3800X’s pricing is the main factor in deciding whether it’s worth buying over the Ryzen 7 3700X. The latter is a little slower at stock speed, especially in multi-threaded tests, and it doesn’t overclock as far.

The price difference is fluctuating too, going between £40 and £60 over the past month. If it’s a £60 difference, that’s money that would be better spent on a bigger SSD, a more premium case or a better CPU cooler.

However, if the difference is small, the promise of a higher overclock or stock speed boost frequencies is worth a small amount of extra cash. Either CPU is currently a great buy, though, especially if you’ll be throwing a range of tasks at your PC.

SPEC

Base frequency3.9GHz
Max boost frequency 4.5GHz
Core Zen 2
Manufacturing process 7nm
Number of cores 8 x physical (16 threads)
IGP None
Simultaneous Multithreading (SMT) Yes
Cache 32MB L3, 4MB L2
Memory controller Dual-channel DDR4, up to 3200MHz
Packaging AMD Socket AM4
Thermal design power (TDP) 105 W
Features Precision Boost 2, Precision Boost Overdrive, FMA3, F16C, SHA, BMI/BMI1 + BMI2, AVX2, AVX, AES, SSE4a, SSE4, SSE3, SSE2, SSE

PROS

  • Most overclockable Zen 2 CPU yet
  • Faster than Core i7-9700K in most tests
  • Excellent all-rounder

CONS

  • Intel chips quicker in some games
  • Cheaper Ryzen 7 3700X isn’t much slower
  • Limited overclocking headroom compared with Intel

VERDICT

One of the best 8-core CPUs around, but the cheaper Ryzen 7 3700X isn’t much slower.

Leave a Comment

Your email address will not be published. Required fields are marked *