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Gaming Performance Comparison

Recommended System Requirements
Game Core i5-9400T 6-Core 1.8GHz Athlon X4 840
Red Dead Redemption 2 7% 135%
Call of Duty: Modern Warfare 21% 75%
Cyberpunk 2077 9% 100%
Halo: Reach 56% 3%
Star Wars: Jedi - Fallen Order 18% 160%
Detroit: Become Human 8% 101%
Borderlands 3 7% 135%
Microsoft Flight Simulator 16% 156%
Resident Evil 3 Remake 0% 120%
FIFA 20 23% 68%

In terms of overall gaming performance, the Intel Core i5-9400T 6-Core 1.8GHz is massively better than the AMD Athlon X4 840 when it comes to running the latest games. This also means it will be less likely to bottleneck more powerful GPUs, allowing them to achieve more of their gaming performance potential.

The Core i5-9400T 6-Core was released over three years more recently than the Athlon X4 840, and so the Core i5-9400T 6-Core is likely to have far better levels of support, and will be much more optimized and ultimately superior to the Athlon X4 840 when running the latest games.

The Core i5-9400T 6-Core has 2 more cores than the Athlon X4 840. 6 cores is probably excessive if you mean to just run the latest games, as games are not yet able to harness this many cores. The cores in the Athlon X4 840 is more than enough for gaming purposes.

The Core i5-9400T 6-Core has 2 more threads than the Athlon X4 840. Both CPUs have one thread per physical core.

Multiple threads are useful for improving the performance of multi-threaded applications. Additional cores and their accompanying thread will always be beneficial for multi-threaded applications. Hyperthreading will be beneficial for applications optimized for it, but it may slow others down. For games, the number of threads is largely irrelevant, as long as you have at least 2 cores (preferably 4), and hyperthreading can sometimes even hit performance.

More important for gaming than the number of cores and threads is the clock rate. Problematically, unless the two CPUs are from the same family, this can only serve as a general guide and nothing like an exact comparison, because the clock cycles per instruction (CPI) will vary so much.

The Core i5-9400T 6-Core and Athlon X4 840 are not from the same family of CPUs, so their clock speeds are by no means directly comparable. Bear in mind, then, that while the Athlon X4 840 has a 1.6 GHz faster frequency, this is not always an indicator that it will be superior in performance, despite frequency being crucial when trying to avoid GPU bottlenecking. In this case, however, the difference is probably a good indicator that the Core i5-9400T 6-Core is superior.

Aside from the clock rate, the next-most important CPU features for PC game performance are L2 and L3 cache size. Faster than RAM, the more cache available, the more data that can be stored for lightning-fast retrieval. L1 Cache is not usually an issue anymore for gaming, with most high-end CPUs eking out about the same L1 performance, and L2 is more important than L3 - but L3 is still important if you want to reach the highest levels of performance. Bear in mind that although it is better to have a larger cache, the larger it is, the higher the latency, so a balance has to be struck.

The Athlon X4 840 has a 512 KB bigger L2 cache than the Core i5-9400T 6-Core, and although the Athlon X4 840 does not appear to have an L3 cache, its larger L2 cache means that it wins out in this area.

The maximum Thermal Design Power is the power in Watts that the CPU will consume in the worst case scenario. The lithography is the semiconductor manufacturing technology being used to create the CPU - the smaller this is, the more transistors that can be fit into the CPU, and the closer the connections. For both the lithography and the TDP, it is the lower the better, because a lower number means a lower amount of power is necessary to run the CPU, and consequently a lower amount of heat is produced.

The Core i5-9400T 6-Core has a 60 Watt lower Maximum TDP than the Athlon X4 840, and was created with a 14 nm smaller manufacturing technology. What this means is the Core i5-9400T 6-Core will consume significantly less power and consequently produce less heat, enabling more prolonged computational tasks with fewer adverse effects. This will lower your yearly electricity bill significantly, as well as prevent you from having to invest in extra cooling mechanisms (unless you overclock).

The Core i5-9400T 6-Core has an on-board GPU, which means that it will be capable of running basic graphics applications (i.e., games) without the need for a dedicated graphics card. The Athlon X4 840, however, does not, and you will probably have to look for a dedicated card if you wish to use it at all.

For in-depth GPU comparisons with the Intel UHD Graphics 630, click on the following GPU overview comparison icon (visible throughout Game-Debate), and choose a GPU from the list to compare against:

On-board GPUs tend to be fairly awful in comparison to dedicated cards from the likes of AMD or Nvidia, but as they are built into the CPU, they also tend to be cheaper and require far less power to run (this makes them a good choice for laptops). We would recommend a dedicated card for running the latest games, but integrated GPUs are improving all the time and casual gamers may find less recent games perform perfectly acceptably.

CPU Core Details

CPU CodenameCoffee Lake RSteamroller
MoBo SocketLGA 1151Socket FM2+
Notebook CPUnono
Release Date23 Apr 201901 Aug 2014
CPU LinkGD LinkGD Link
Approved

CPU Technical Specifications

CPU Cores6vs4
CPU Threads6vs4
Clock Speed1.8 GHzvs3.4 GHz
Turbo Frequency3.4 GHzvs3.8 GHz
Max TDP35 Wvs95 W
Lithography14 nmvs28 nm
Bit Width64 Bitvs64 Bit
Virtualization Technologynovsno
Comparison

CPU Cache and Memory

L1 Cache Size384 KBvs-
L2 Cache Size1536 KBvs2048 KB
L3 Cache Size9 MBvs-
Max Memory Size-vs32 GB
Memory Channels-vs2
ECC Memory Supportnovsno
Comparison

CPU Graphics

GraphicsIntel UHD Graphics 630
Base GPU Frequency350 MHzvs-
Max GPU Frequency1150 MHzvs-
DirectX12vs-
Displays Supported-vs-
Comparison

CPU Package and Version Specifications

Package Size37.5mm x 37.5mmvs-
Revision-vs-
PCIe Revision-vs-
PCIe Configurations-vs-

Gaming Performance Value

Performance Value

CPU Mini Review

Mini ReviewThe Core i5-9400T 6-Core 1.8GHz is a mid-range CPU based on a refinement of the 14nm++ Coffee Lake microarchitecture. The 'T' suffix indicates this a low-power draw variant. It offers 6 physical cores (6 logical), initially clocked at 1.8GHz, which may go up to 3.4GHz using 6 cores with Turbo Boost. The i5-9500F has 9MB of L3 Cache. This chip supports up to 128GB DDR-2666 MHz memory and features Intel UHD 630 integrated graphics. Among its many features, Turbo Boost 2.0, Optane Memory Support, and Virtualization are activated, and its multiplier is not unlocked. This Core i5-9500T CPU offers average gaming performance and should not be a major bottleneck in any modern gaming PC in 2019. It will be able to play all modern games at 60fps comfortably on ultra graphics performance at any supported resolution without being a hindrance to the accompanying GPU. However, performance may become bottlenecked if playing at 144Hz and 1080p or lower screen resolution.Athlon X4 840 is a Quad Core based on the 28nm, Streamroller microarchitecture.
We will add more information, once it becomes available.

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