Cx86! - control program for Cyrix/IBM/ST/TI CPUs

Certainly all names of companies and their products contained here are their property, not mine.

The page was updated on 1997-01-24.

Cyrix 5x86/6x86 (and 486) control program - Cx86!

Current version - 1.20 (97-01-24)

This tiny utility allows for setting all important control bits inside Cx 5x86, 6x86 and older 486 CPUs, making it run faster and/or crash your system :-). It was designed for both users and hackers. Normal users can use command line options to enable or disable particular performance features. Hackers can use debug mode to examine and modify individual control registers.

Warning

Use at your own risk - absolutely no warranty. Please report all program bugs to me. I had to make many significant changes to the code and had no time to test it, so I count on your help.

History and features

After releasing version 1.0, supporting only 5x86, I have received many requests for the description of particular feature bits. So the new shareware version 1.1 contained complete description of all the major features of the CPU. Version 1.20 features include:

full control of all common features from command line (including CPUIDEN of course)

PIPELOOP-equivalent slowdown of LOOP instruction (useful for Clipper and some other nasty programs)

far COF hits enable control (like in IBM M1OPT)

full cache control via CR0 (for 486DLC)

symbolic names for all known features in 5x86/6x86 and most of important controls in 486

enhanced debug mode (hacker mode)

Downloading

Cx86! is distributed in a very funny form. The file you can download - Cx86!.EXE. is actually .COM file. DOS doesn't care about extensions, but if you want to run it from Windows, you better rename it back to Cx86!.COM. To read the description, view the file with any text viewer or editor - it contains only ASCII characters. This way you have both executable and description in single file. Please tell me how you like this form of distribution. If you dislike it, next releases will be distributed in more conventional way.

Just in case you prefer some other competitive products, you may have a look at similar stuff by Peter Moss - here
or visit "Bryan Davis good Cyrix page"

The End