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Gaming Performance Comparison

Recommended System Requirements
Game APU A6-6420K Dual-Core Phenom 9550 Quad-Core
Cyberpunk 2077 196% 131%
Assassins Creed: Valhalla 299% 211%
Call of Duty: Black Ops Cold War 187% 124%
Hitman 3 299% 211%
Grand Theft Auto VI 387% 280%
FIFA 21 177% 116%
Far Cry 6 368% 265%
Genshin Impact 124% 75%
World of Warcraft: Shadowlands 361% 260%
Watch Dogs Legion 299% 211%

In terms of overall gaming performance, the AMD Phenom 9550 Quad-Core is significantly better than the AMD APU A6-6420K Dual-Core 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 APU A6-6420K Dual-Core was released over three years more recently than the Phenom 9550 Quad-Core, and so the APU A6-6420K Dual-Core is likely to have far better levels of support, and will be much more optimized and ultimately superior to the Phenom 9550 Quad-Core when running the latest games.

The Phenom 9550 Quad-Core has 2 more cores than the APU A6-6420K Dual-Core. With 4 cores, the Phenom 9550 Quad-Core is much less likely to struggle with the latest games, or bottleneck high-end graphics cards when running them.

The Phenom 9550 Quad-Core has 2 more threads than the APU A6-6420K Dual-Core. 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 APU A6-6420K Dual-Core and Phenom 9550 Quad-Core 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 APU A6-6420K Dual-Core has a 1.8 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 Phenom 9550 Quad-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 Phenom 9550 Quad-Core has a 1024 KB bigger L2 cache than the APU A6-6420K Dual-Core, and although the APU A6-6420K Dual-Core 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 APU A6-6420K Dual-Core has a 30 Watt lower Maximum TDP than the Phenom 9550 Quad-Core, and was created with a 33 nm smaller manufacturing technology. What this means is the APU A6-6420K Dual-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 APU A6-6420K Dual-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 Phenom 9550 Quad-Core, 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 Radeon HD 8470D, 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 CodenameRichlandAgena
MoBo SocketSocket FM2Socket AM2+
Notebook CPUnono
Release Date01 Mar 201427 Mar 2008
CPU LinkGD LinkGD Link
Approved

CPU Technical Specifications

CPU Cores2vs4
CPU Threads2vs4
Clock Speed4 GHzvs2.2 GHz
Turbo Frequency4.2 GHzvs-
Max TDP65 Wvs95 W
Lithography32 nmvs65 nm
Bit Width64 Bitvs64 Bit
Max Temperature70°Cvs70°C
Virtualization Technologynovsno
Comparison

CPU Cache and Memory

L1 Cache Size128 KBvs512 KB
L2 Cache Size1024 KBvs2048 KB
L3 Cache Size-vs2 MB
Memory Channels-vs2
ECC Memory Supportnovsno
Comparison

CPU Graphics

GraphicsRadeon HD 8470D
Base GPU Frequency800 MHzvs-
Max GPU Frequency-vs-
DirectX11.1vs-
Displays Supported-vs-
Comparison

CPU Package and Version Specifications

Package Size-vs-
Revision-vs-
PCIe Revision-vs-
PCIe Configurations-vs-

Gaming Performance Value

Performance Value

CPU Mini Review

Mini ReviewAPU A6-6420K Dual-Core is a performance CPU based on the 32nm, Piledriver architecture.

It offers 2 Physical Cores (2 Logical), initially clocked at 4.0GHz, which may go up to 4.2GHz and 1MB of L2 Cache.
Among its many features, Turbo Core and Virtualization are activated and the processor has the clock multiplier unlocked, meaning it can be overclocked easily.

The processor integrates weak Graphics called Radeon HD 8470D, with 192 Shader Processing Units, clocked at 800MHz, which share the L2 Cache and system RAM with the processor.
Both the processor and integrated graphics have a rated board TDP of 65W.

It offers average performance. This means it will become a bottleneck in some demanding applications.
Phenom 9550 Quad-Core is a performance processor based on the 65nm, K10 architecture.

It offers 4 Physical Cores (4 Logical), clocked at 2.2GHz and 2MB of L3 Cache.
Among its many features, Virtualization is activated.

The processor DOES NOT integrate any graphics. and has a rated board TDP of 95W.

It offers average performance. This means it will become a bottleneck in some demanding applications.