This Article was last modified in July, 1998.
After Cyrix's (somewhat) great success with their 6x86, they decided to continue, and produced the 6x86MX. Some people are confused as to which processor the 6x86MX is competing with, the Pentium MMX, or Pentium II. In business applications, the 6x86MX greatly outperforms any Pentium MMX, and even beats the Pentium II in some respects, however, the 6x86MX falls far behind the Pentium MMX in games and other 3D applications due to its' weak FPU. So, in my opinion, this CPU should be placed somewhere in between the Pentium MMX and the Pentium II.
The 6x86MX processor offers significant enhancements over the 6x86 processor. These enhancements enable the 6x86MX processor to achieve higher performance at any given clock speed.
The 6x86MX design quadruples the internal cache size to 64-KBytes, triples the TLB size, and increases the frequency scalability to 200 MHz and beyond, relative to the 6x86 processor. Additionally, it features 57 new MMX instructions that speed up the processing of certain computing-intensive loops found in multimedia and communication applications. The 6x86MX processor also contains a scratchpad RAM feature, supports performance monitoring and allows caching of both SMI code and SMI data.
The 6x86MX processor features a superpipelined architecture that increases the number of pipeline stages to reduce timing constraints and increase frequency scalability. Advanced architectural techniques include register renaming, out-of-order completion, data dependency removal, branch prediction and speculative execution. These design innovations eliminate many data dependencies and resource conflicts.
|3D Performance ||75%|
|Overall Performance ||95%|
Overclockability: As in the 6x86, in order for Cyrix to keep the prices of the 6x86MX down, they had to be optimized as much as possible, and therefore there is not much room left for improvement. In addition, these chips run extremely hot and might possibly overheat if they are overclocked for too long.
3D Performance: The FPU performance of a 6x86MX is very weak. So although the MMX enhancements in this processor might increase the speed of games slightly, the fact that this CPU has such a weak FPU seriously decreases performance in FPU intense applications, such as Quake.
Overall Performance: The 6x86MX performs a bit faster than it's equivalent Pentium MMX or (in some cases) Pentium II, in terms of typical business applications. However, the 6x86MX falls behind in 3D applications and games. Also, the 75mhz bus speed of these processors help significantly to increase overall system performance.
Upgradability: These CPU's are just as upgradable as any other Socket7 processor, especially since they use the new split-voltage technology.
Compatibility: Since almost all PC games and applications are fine tuned for Pentium CPU's, the 6x86MX suffers some problems with some specific software. However, Cyrix has come out with patches to fix many of the problems, which can be downloaded from their website.
Price: 6x86MX CPU's are MUCH cheaper than their Pentium II competitors, and even cost significantly less than their Pentium MMX competitors. For the (very small) price you pay, you get a great CPU, the business performance is stellar, and in many cases better than the Pentium II, however the 3D performance is lagging somewhat behind. My recommendation: if you are a hardcore gamer, go for a K6, Pentium MMX, or (if you can afford it) Pentium II. If you're anything else, go for the 6x86MX.