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Performance of Future 6x86MX CPUs


Last week I received a new 6x86MX CPU that turned out to be very overclockable. We are all very interested how higher clock speed 6x86MX CPUs will perform and this page shall give you only some ideas how it will look.

I performed the test on a AOpen AX5T rev. 3, which is one of the fastest Socket 7 motherboards and also capable of 83 MHz bus speed. This board is also running very stable, which makes it to one of the best 'overclocking motherboards'.

This page is not meant to be particulaly comprehensive, because I will do the detailed testing of the 6x86MX on my upcoming new CPU Guide.

Windows 95 Performance

Business applications under Windows 95 is where the 6x86MX performs particularly well, as you could already see on my 6x86MX Review Page. The 225/75 MHz version will be called PR266 for a reason, because it's just as fast as the Pentium II at 266 MHz. I'd say that this is an impressive performance indeed. We could also already see in my previous review that the bus speed doesn't have the same high impact as on the Intel Pentium and the AMD K6. A 6x86MX at 208 MHz with a bus speed of 83 MHz is definitely slower than at 225 MHz. You can also see that a 200 MHz version will hardly perform better than the known PR233 (187.5/75 MHz) version. Cyrix/IBM could release this CPU under the same PR rating only for people that want to avoid 75 MHz bus speed. Unfortunately there was no chance to run the 6x86 I tested at 233/66 MHz, it would crash each time I tried. However can we expect the 233 MHz version to perform pretty much the same as the 225 MHz version, which would be a 66 MHz bus speed alternative for the PR266.

Windows NT 4 Performance

Under NT the 6x86 isn't quite as great, but the PR266 will still be able to compare to the Pentium II 233.