The Towering 64-Core Threadripper 3990X Update

At times there are earthquakes, and at times there are hurricanes. Volcanoes sometimes erupt, and meteors sometimes strike the earth. And when they are in the mood, sometimes AMD releases a 64-core, 128-thread consumer CPU that makes you sit up and wonder if you are in a dream. 64 cores! Sixty (60) four (4) cores (cores)!

Remember when 6-core CPUs became normal barely 2 years ago? “Haha, you foolish weaklings”, says AMD, as it unveils a CPU that is TEN TIMES more powerful. We need to send a letter to Dr. Lisa Su to inform her that this is a mistake, and it is not the year 2030 yet!

The Good News about the TR 3990X

Let us put things in perspective. Instead of looking at CPU trends among peasants (the dual-core general population), let’s look at a group that is known for chasing better performance whenever possible: Gamers. From Steam’s hardware survey (checked February 2020), we get the following:

The majority of gamers (50%) use only 4-core CPUs. The overwhelming majority (90%) use 6-cores or lower. So when we say that AMD’s 64-core behemoth is ten times more powerful than the average, that is not an exaggeration! Please stop making us feel small and puny, AMD!

But core count, like age, is just a number. No one is buying a CPU for the number on the sticker. How well does the TR 3990X perform? Is it worth the cheeky price of $3990? Does it require a thermonuclear reactor to power it up, and a frozen Arctic torrent to cool it down? Did AMD cheat and lower the operating frequency so low that the 3990X has the single-threaded performance of a pocket calculator? Let us take a closer look.

We start with the good news: The 3990X’s normal speed is 2.9GHz, but it can turbo to 4.3GHz. Is that the fastest? No, but it is very good. In single-threaded performance, the 3990X is only a small 3% behind our benchmark CPU, the 3900X. The TDP is 280W, which is high, but the same as the 3960X and 3970X. It does not run any hotter than those, and here is Linus benchmarking it with a normal aircooler. All is very good… so far.

When the conditions are right, the 3990X wins by very large margins. (Image from Anandtech)

The Bad News about the TR 3990X

If we started with good news, then there must be bad news. To anchor our expectations, let us take the CPU that we use as the baseline for performance, the excellent R9 3900X, and do some approximate calculations:

 

    • The 3900X costs $500.
    • The 3990X costs $4000.
    • That is an increase of 8x in price.
    • The 3900X has 12 cores.
    • The 3990X has 64 cores.
    • Uh oh. That is an increase of 5x in core count.
    • Since it is the benchmark CPU, the 3900X is rated at 100% for multi-threaded performance.
    • The 3990X scores 350% in multi-threaded. That is a performance increase of only 3.5x!

 

So you pay 8x more, but you only get 5x the cores, and just 3.5x the performance! Ouch! That is less than half the performance you should be getting, in theory. But why is that? It is a combination of OS and software.

For the OS: According to Anandtech, the typical version of Windows 10 (home or pro) will not handle the 128 threads properly. You will need to either turn off hyper-threading, or switch to Windows 10 Workstation or Enterprise. So unless you are willing to fork out more $$$ and take the trouble to make the switch, the 3990X is not going to do much for you.

On the software side: Extremely few pieces of non-benchmarking software can take advantage of 128 threads. In fact, even if we set aside normal workloads and exclusively check benchmark software results, we find that many of them show only a moderate win for the 3990X when compared with the 3970X. The 3970X is half a 3990X, with 32-cores.

In other words, the 3990X is so powerful that benchmarking software whose sole job is to measure power… cannot keep up! And no, that is not good. If your CPU cannot stretch its wings under (literally) the most ideal circumstances, then what good would it be with normal workloads?

When things are at their worst: Just change the OS and enable hyper-threading, and the 3990X defeats itself. (Image from Anandtech)

Unfortunately, we are left with little choice but to come to an unpleasant conclusion: The world is not ready to handle the mighty Threadripper 3990X. In some rare instances, when the right software is running on the right operating system and the 3990X can be fully utilized, the 3990X pulverizes everything that stands in its way. The other 99% of the time, however, you get better results with much cheaper CPUs.

There are two vehicles here. One of them represents the 3990X. The other represents something that is actually useful to 99.99% of normal consumers. (Image from machines4u.com.au)

Conclusion:

Time heals all wounds, including software-related injuries. There is little doubt that at this very moment, every software vendor is updating their software so that it can take advantage of a 128-thread consumer CPU. In time, a 128-thread CPU will become more recommendable as the computer world adapts to accommodate it.

In time, a 128-thread CPU will cost less and less. Maybe it will cost only $1000 in 4 years? Maybe $250 in 8? When that happens, the child (or grandchild) of the Threadripper 3990X will take its place in our tier list. For now though, this supremely-powerful-but-mostly-unusable $4000 CPU is going to stay on the shelf and off our chart.

Yes, the majestic Threadripper 3990X is the undisputed king… of a future world.

Sources:

(P.S: “Wait!“, you say. “This cannot be all! What about competing CPUs from Intel?” you ask. At the moment, CPUs from Intel do exist, but competition does not. In fact, with the 3990X being what it is, Intel only deserves a couple of sentences in italics… as a post-script afterthought.)