Cyrix Processors
The Future's Built In Demo Reseller Network Where to Buy Cyrix



Technical FAQ Section

Q. What is the Cyrix 6x86™ processor?
A. The sixth-generation 6x86 processor, formerly the M1, is a high-performance superscalar, superpipelined, x86 processor.

Q. Why is Cyrix, a microprocessor manufacturer, selling PCs?
A. We want people to know about the outstanding performance advantages of the Cyrix 6x86 processor. Marketing 6x86 PC systems is a key element in promoting Cyrix processors to end users, thus promoting demand for our OEM customers' 6x86-based PCs.

Q. Will Cyrix continue selling processors to OEMs?
A. Yes. The vast majority of Cyrix processors will be sold to OEMs and PC dealers who will market 6x86-based PCs under their own brand.

Q. How does it differ from the Pentium® processor?
A. Most significant are the architectural differences which result in the 6x86 processor's superior performance gains. While both the 6x86 and Pentium® processors are superscalar and contain an 80-bit floating point unit and a 16-KByte primary cache, other architectural features are found only on the 6x86. The 6x86 processor's integer and floating point units are optimized for maximum instruction throughput by using advanced architectural techniques including register renaming, out-of-order completion, data dependency removal, branch prediction and speculative execution. These design innovations eliminate many data dependencies and resource conflicts to achieve high performance.

Q. What is the difference between the Cyrix 6x86 and 5x86 processor?
A. There are significant differences between these two Cyrix processors. The 5x86 processor, formerly the M1sc, is pin-compatible with a 486. However, the 5x86 uses many fifth-generation features (branch prediction, data forwarding, superpipelining, etc.) to achieve performance equal to Pentium processors. The goal for the 5x86 was to achieve an efficient design, obtaining the highest performance possible using the fewest transistors to obtain entry-level Pentium processor performance. A 120 MHz 5x86 performs on par with a 90 MHz Pentium processor.

The Cyrix 6x86 processor is a high-performance, sixth-generation CPU that is P54C socket-compatible. It incorporates a 64-bit external data bus (5x86 use a 32-bit external data bus) and a variety of innovative architectural features that enable it to outperform higher-megahertz Pentium processors to achieve best-in-class performance. Additional design information can be found in the 6x86 Processor Brief.

Q. Can I use the Cyrix 6x86 processor as an upgrade for my 586 computer?
A. Cyrix doesn't sell the 6x86 processor as an upgrade processor. However, some dealers or resellers may offer a 6x86 upgrade solution.

Q. Will future 6x86 processors work in the 6x86-based PC I buy today?
A. Yes. Cyrix offers users of 6x86-based PCs an easy path to higher performance for Windows NT and to MMX technology that protects today's PC investment. The next version of Cyrix's 6x86 processor, code-named M2, will provide optimum performance on 32-bit software and will be fully MMX compatible. This new processor will leverage today's 6x86 motherboard platforms, allowing plug-in upgrades for today's buyers of 6x86-based PCs. Purchasers can buy a 6x86-based PC now, with a guaranteed path to future technology via an M2 upgrade.

Q. Is the 6x86 processor compatible with existing software?
A. Yes. The 6x86 is compatible with x86 software and all popular x86 operating systems including Windows® 95, Windows, Windows NT, OS/2, DOS, Solaris and UNIX. Additionally, the 6x86 processor has been certified Windows 95 compatible by Microsoft. While we cannot test every x86 application available, the Software Compatibility List is updated frequently to provide an index of hundreds of applications and programs that have been tested on systems using the Cyrix 6x86 processor.

Q. Is the Cyrix 6x86 processor certified for Windows 95?
Designed for Windows 95A. Yes. Cyrix tested the 6x86 processor on hundreds of x86 software applications to ensure compatibility with new and existing software. Additionally, the 6x86 processor (up to and including the 166+ processor performance class) has been certified Windows 95 compatible by Microsoft. We're licensed by Microsoft to use the "Designed for Windows 95" logo for these classes; the P200+ performance class is under Microsoft testing.

Q. Can the 6x86 processor run 16-bit and 32-bit software?
A. Yes. The 6x86 was designed to run existing 16-bit software as well as the latest 32-bit software.

Q. What are the performance results for the 6x86 processor?
A. We list full, competitive 6x86 performance results for several industry benchmarks. The tests show that the 6x86 processor outperforms higher-megahertz Pentium processors in each performance class.

Q. What is this new performance, or P-rating, system Cyrix is using?
A. The P-rating system was jointly developed by Cyrix, IBM Microelectronics, SGS-Thomson Microelectronics, and Advanced Micro Devices. The P-rating system allows end-users to base purchases on relative PC performance levels rather than just the clock speed (MHz) of the processor. The new evaluation system relates the results of industry-standard benchmarks to what is achieved by an Intel Pentium processor of a given frequency. For example, a processor with a P150 rating would have performance comparable to a 150 MHz Pentium processor, regardless of its actual clock speed.

Q. Why was the P-rating developed?
A. Clock frequency (MHz), while important, is no longer an accurate or consistent measure of CPU performance. Architectural differences between processor designs add another variable to the equation. With the P-rating in place, a PC buyer can easily evaluate all personal computer processors for a given performance category -- without scrutinizing the architectural merits of the different processors.

MicroDesign Resources (MDR) Labs conducted independent performance testing of the 6x86 processor. Commenting on the P-rating methodology, Michael Slater, president of MicroDesign Resources and publisher of the Microprocessor Report, said, "This is the first comprehensive and credible method for comparing competing processors based on the relative performance they bring PC users under real-world conditions. It standardizes test system configurations based on commercially available components, and it uses the most widely recognized and utilized application-based benchmark tests. I expect the new P-rating methodology to achieve broad industry acceptance."

Q. How does the P-rating work?
A. The P-rating process uses a standardized system configuration and application-based benchmark tests to establish a performance, or 'P,' rating relative to a Pentium processor of a given frequency (MHz). This levels the playing field and allows the measurement of relative processor performance under real-world conditions, regardless of the processor's clock speed (MHz) or architecture.

Q. What benchmark test is used in the P-rating?
A. Ziff-Davis Winstone® 96 is used because it is a real-world, application-based benchmark that contains the most popular software applications (based on market share) that run on a Pentium processor. Winstone 96 also is the most widely used benchmark, and is freely distributed and available.

Q. Why is there a plus mark in each 6x86 processor name?
A. For the 6x86 processor, a P+ designation is used to indicate better performance.

Winstone 96 6x86-Pxxx+ > Winstone 96 Pentium-xxx
xxx = P-rating or Pentium megahertz

For example, a 6x86 processor with a P-rating of "P166+" (regardless of processor name and clock speed) indicates performance faster than a 166 MHz Pentium processor. The plus mark indicates performance that consistently exceeds the same Pentium processor megahertz level.

Q. What 6x86 processors are currently available?
A. The 6x86-P166+ (133 MHz), 6x86-P150+ (120 MHz), and 6x86-P133+ (110 MHz) processors are in volume production now. Volume production of the 6x86-P200+ (150 MHz) is planned for August.

Q. What is the cost of the 6x86 processor?
A. Prices are subject to change. The pricing (as of August 9, 1996) is:

All prices are for quantities of 1,000. For additional pricing information, please contact the Cyrix Processor Support Desk.

Q. How can I purchase the 6x86 processor?
A. Computer manufacturers around the world can buy in volume quantities directly from Cyrix. PC integrators, VARs, dealers, resellers, and retailers can purchase Cyrix processors through an independent Cyrix U.S. distributor or worldwide distributor. End users can purchase a computer that uses the 6x86 from local PC dealers. There is more information available on purchasing Cyrix processors.

Q. What if I have more questions?
A. Please contact the Cyrix Processor Support Desk.

| What's New | Product Details | Dealer Info & Resources | Support Desk | Page Top |

6x86 Processor Technical FAQs


Q.What does the C028, 3.52V (C028), or 3.52V mark on top of the chip mean?
A. C028 or 3.52V (028): The device operates at a nominal voltage of 3.52V. You should use the appropriate voltage settings on the motherboard (often documented as VRE, 3.52V or 3.4-3.6V range). C016 or 3.3V (016): The device operates at a nominal voltage of 3.3V. You should use the appropriate voltage settings on the motherboard.

Q.What does the 110MHz on the 6x86-P133 chip mean?
A.The operating frequency is 110MHz (55MHz bus) but the device has been verified to perform better than a Pentium-133.

Q.Which motherboards work with the 6x86?
A. Refer to the Cyrix recommended 6x86 motherboard list for information on P166+ certified platforms.

Q.I have found other motherboards that work with the 6x86 but are not on your recommended list. Why not?
A.It could be one of several things: the manufacturer has not given us a sample, has not approved the listing, or it is going through testing now, but has not completed the test suite.

Q.How do I know my motherboard can support the 55/110 MHz 6x86-P133?
A.The board or documentation should have jumper settings defined for 55/110MHz. Refer to the Cyrix recommended 6x86 motherboard list for a complete list of platforms that support the P133+.

Q.What board MHz setting do I use for each P-rating?
A.P120+ = 50MHz CPU bus with a 2X clock (50/100MHz)
P133+ = 55MHz CPU bus with a 2X clock (55/110MHz)
P150+ = 60MHz CPU bus with a 2X clock (60/120MHz), same as Pentium-120
P166+ = 66MHz CPU bus with a 2X clock (66/133MHz), same as Pentium-133
P200+ = 75MHz CPU bus with a 2X clock (75/150MHz)

Q.The motherboard has several voltage settings. Which one is right for the 6x86?
A.It depends on which CPU you have. The markings on top of chip will indicate which voltage setting is appropriate.

Q.Why does the BIOS recognize my 6x86-P133 chip as a 6x86-P120?
A.The motherboard jumpers are incorrectly set to 50/100MHz or the motherboard does not support 55/110MHz.

Q.Does Cyrix ship a cooling fan/heatsink with the 6x86 processor?
A.Yes, each processor is shipped with a certified heatsink/fan. We do this to guarantee a quality heatsink/fan is in use to ensure proper operation of the CPU.

Q.Why does the processor get hot?
A.The CPU may have an inadequate heatsink/fan. The certified heatsink/fan we ship with each processor is guaranteed to keep the CPU temperature within the specifications.

Q.The Cyrix cooling fan doesn't fit on my boards. What do you recommend?
A.The Cyrix certified heatsink/fan should work in most boards. However, Cyrix can ship the CPU without a heatsink/fan if you would like to find your own heatsink/fan to fit on board. If the clip is a problem (components too close to socket 7), use the Cyrix verified heatsink/fan solution available from VEMALINE that slides onto the CPU package (Part No. HTS108). Another alternative is to use a different motherboard. Refer to the Cyrix recommended 6x86 motherboard list for more information.

Q.Does Cyrix have a heatsink/fan solution that is 90 degrees oriented so the voltage regulator can be cooled?
A.Cyrix recommends having an adequate heatsink on the voltage regulator. If further cooling is deemed necessary, the VEMALINE HTS108 solution can be used. This solution can be oriented to blow air to the voltage regulator.

Q. When I run Windows 95 on my 6x86 computer, the Windows 95 control panel system information identifies the CPU as a 486. Why?
A. The algorithm used in Windows 95 to detect the CPU was completed before the Cyrix 686 was released and therefore the Cyrix 686 responds to the algorithm just as a 486 does. To verify that your system is using the 6x86 microprocessor, please reference your computers BIOS startup screen. In addition, the following software utilities identify the 6x86 CPU correctly: Diagsoft QA Factory 6.02 and QA Plus/FE 5.42; Quarterdeck Manifest 4.01; and PC Doctor Rev 1.5.162 from Watergate Software. Cyrix will update this site with new software utilities that can detect a 6x86 CPU in the future. Please note that the 6x86 processor was certified by Microsoft for Windows 95, and Windows 95 performance results are available.

Q. When I run 3D Studio and Clipper on my 6x86-based PC, the programs are stalling. What's the solution?
A. Both 3D Studio and Clipper Applications use software timing loops in the code. The 6x86 processor executes these loop instructions faster than previous x86 CPUs which interferes with timing dependent code in both software programs. Solution: Download the pipeloop.exe file and put it in your autoexec.bat file. This utility inserts a delay in the loop instruction. The utility is not memory resident. NOTE: This file may not correct all timing issues. Other solutions will be listed when available.


| What's New | Product Details | Reseller Network | Where To Buy | Support Desk | Page Top |
| Processors | PC Systems | Corporate Info | Search | Contact | Text Only | Home |

Copyright © 1995-1996 by Cyrix Corporation, Richardson, TX, U.S.A.