Conclusion
There is no clear-cut answer to the question about how much CPU is needed for gaming. It depends on the individual game and desired detail levels. Different games, and even levels of detail in a game, will stress difference components of the system, so it’s important to have a balanced system if you hope to enjoy a wide range of games. Buying too much GPU is a waste of money if the CPU is holding back your performance. Likewise, not enough GPU will limit the resolution, detail levels and eye candy you can enjoy.
We clearly see from Crysis, Call of Duty 4, and Oblivion, that single-core CPUs now struggle in games and will at least limit the detail levels you can play at. Enemy AI and impressive physics effects are often too much for a single-core CPU to handle on top of its other tasks. In some very CPU-demanding titles, you may not even be able to tweak acceptable performance with a single-core processor. Also keep in mind that the minimum FPS on a single-core CPU will often drop much lower, making for choppy game play. Socket 754 and 939 owners on single cores should see all this as a sign that their system has limited life for future games.
A dual-core CPU is pretty much the standard recommended CPU for current games. In the newest games we tested, we see that our X2 4200+ dual core is easily able to outperform a higher-clocked single-core chip. With higher average and more consistent minimum frame rates, they will provide the much better gaming experience. Socket AM2 owners wanting to play games should be on a dual-core CPU for sure.
What about clock speeds? Are they important? Well, we can easily see our X2 5600+ consistently pulling away from the other two CPUs with both the 8800 GS and the HD 4850. As long as we are not GPU-limited, CPU clock speeds were making a marked difference. The lower-clocked X2 4200+ even struggled in our testing, and was at times barely able to maintain a 30 FPS average even at low resolutions. If you are buying a mid- or high-end GPU and do not want your CPU to limit your playable settings in the latest games like Crysis or Call of Duty 4, or even Oblivion, Socket AM2 owners will need to run an Athlon 64 X2 at high clock speeds. A clock speed of 2.4 GHz and below isn’t always going to cut it and sometimes you’ll find the higher the clocks, the better off you are. Socket 939 owners should see this as a good reason not to buy an overpriced low-clocked dual-core for their machine.
Anyone seeking very high-end GPUs or multi-GPU solutions could also step up to an Intel Core 2 Duo or Quad with decent clock speeds, either out of the box or user overclocked. But that doesn’t mean you should blow all your money on a QX6850 or even E8600. They are excellent processors, but a gamer definitely should not skimp on the graphics card, as given enough CPU power, it will be the biggest limiting factor for the resolution, detail levels and amount of eye candy like FSAA/AF that remain playable.
If you are stuck on an Athlon 64 single-core CPU with no upgrade options and no budget for a new system, all hope is not lost. There are some newer games and also plenty of great titles in the bargain bin that run well on single-core CPUs. Spending up to $100 or so on a nice bargain card like the 8800 GS, 9600 GSO, HD 3850, HD 4670, 9600 GT, HD 3870, 8800 GT, or 9800 GT will allow you to max out many of these older or single-threaded games if your current GPU is too weak. In newer titles, the detail levels will need to be reduced to relieve the demand on the CPU, so some of your potential performance of a new GPU is being thrown away. To compensate, the added power of a better video card can allow for high resolutions and FSAA/AF levels making for a better gaming experience.
Athlon XP and sub-3.0 GHz Pentium 4 owners are going to be in worse shape than Athlon 64 owners and are even going to find themselves below minimum spec for some games. Just keep in mind that even the best single-core CPUs are below recommended specs for many if not most of the latest games, and will limit the playability of these titles. Adding even the beefiest new PCI Express gaming card will not mean you can play these games with all details turned up and checked. This trend will only continue to get worse, so if it hasn’t already happened, be prepared to find out that a system upgrade will be required for an upcoming game that’s high on your wish list.
Lastly, before buying any hardware for a game your system is struggling in, keep an eye on the game’s recommended system specs, and if a dual-core CPU is recommended, it’s likely multi-threaded and chances are good that single-core CPUs will limit the playable detail levels, regardless of the graphics card paired with it. A new graphics card may still be what is required to gain an acceptable balance of performance and detail levels in the game, but following the advice this article offers can help avoid the disappointment of spending big bucks on too good of a gaming card only to find out your processor is preventing it from offering the performance you expected.