ÛÛÛÛÛÛ» ÛÛ» ÛÛ» ÛÛÛÛÛÛ» ÛÛ» ÛÛ» ÛÛ» ÛÛÉÍÍÍͼ ÈÛÛ» ÛÛɼ ÛÛÉÍÍÛÛ» ÛÛº ÈÛÛ»ÛÛɼ ÛÛº ÈÛÛÛÛɼ ÛÛÛÛÛÛɼ ÛÛº ÈÛÛÛɼ ÛÛº ÈÛÛɼ ÛÛÉÍÍÛÛ» ÛÛº ÛÛÉÛÛ» ÈÛÛÛÛÛÛ» ÛÛº ÛÛº ÛÛº ÛÛº ÛÛɼ ÛÛ» ÈÍÍÍÍͼ Èͼ Èͼ Èͼ Èͼ Èͼ Èͼ Technical Support BBS ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ³ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿³ ³³Thanks for calling the Cyrix Technical Support BBS.³³ ³³Address all messages needing a Cyrix response to ³³ ³³the SYSOP. Otherwise you may not recieve a timely ³³ ³³response. ³³ ³³Cyrix Technical Support now has an internet address³³ ³³This is a simple question and answer address for ³³ ³³Tech. Support. Address is tech_support@cyrix.com ³³ ³ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ³ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ CYRIX 386 to 486 UPGRADE MICROPROCESSOR Information Sheet Product Description The Cyrix 386 to 486 Upgrade Microprocessor is the only single chip microprocessor upgrade designed for 386DX-16, 20 or 25 MHz computers. It is based on Cyrix 486 technology and features clock doubling, a 1K on chip cache, Cyrix cache coherency technology (patent pending), fast I/O and a clock skewing correction circuit. The result of these features are the benefits of compatibility, data integrity and high performance. Key Features and Benefits Single Chip Design Direct microprocessor upgrade. High quality, dependability and no space problems. Supports 486 Instruction Set Runs all of today's and tomorrow's 386 and 486 software. Clock Doubling Enhanced performance with the Upgrade Microprocessor running at twice the computer's bus clock speed. On Chip 1K Cache with Cache Coherency Support (patent pending) High performance with data integrity Fast I/O High performance from improved input/output operations of data between the microprocessor and the computer's bus. Clock Skewing Correction Circuit Ensures compatibility with systems whose internal clock may be variable. Supports DOS, Windows and OS/2 Operating Systems Universal Software Compatibility. Easy installation No additional system modifications. III) Implementation of Key Features 1) Single Chip Design - The Upgrade Microprocessor comes in a single chip form factor the same size as the 386DX microprocessor. This single chip design ensures long term reliability and eliminates any physical space problems found with board style upgrades. 2) Supports 486 Instruction Set - Based on Cyrix's Cx486 design, the Upgrade Microprocessor will support all 386 and 486 software applica- tions available today. This also ensures compatibility for all future software designed under 386 and 486 industry standards. 3) Clock Doubling - Clock doubling greatly enhances performance of all applications, particularly those applications that are processor intensive. The Upgrade Microprocessor will run at a speed twice that of the 386DX microprocessor. For example, if the 386DX microprocessor being upgraded runs at 20MHz, the Upgrade Microprocessor will run at twice the speed, or 40MHz. Since the system's clock is not adjusted or changed, no additional FCC approval is required for the Upgrade Microprocessor. 4) On Chip 1K Cache - Significant performance gains are achieved withthe Upgrade Microprocessor's on chip cache. This cache is a memory areawithin the Upgrade Microprocessor that holds data ready to be used by the processor. Since this data is in the processor, it can be accessed more quickly than retrieving from the system's memory. This feature is not found in 386DX microprocessors. 5) Cache Coherency - Data integrity is assured with Cyrix's cache coherency technology (patent pending). Since 386 systems are not designed to support an on chip cache, this technology ensures data integrity between the internal cache and external memory. 6) Fast I/O - This is an enhanced feature Cyrix has incorporated into the Upgrade Microprocessor which is not found in other 386 and 486 micro- processors. This feature allows the processor to continue processing during input/output functions to other components of the computer like printer ports, d isk drives and graphic boards. Fast I/O will significantly improve video and disk performance where many I/O func- tions take place. 7) Clock Skewing Correction - This feature ensures compatibility where other upgrade products do not. Since tolerances vary with many 386 computer system clocks, Cyrix has implemented in the Upgrade Microprocessor this mechanism allowing it to adjust to system clock variances. 8) Supports DOS, Windows and OS/2 - We said earlier that 386 systems do not support an on chip cache as found in the Upgrade Microprocessor. In order to turn on the cache a small program is automatically run when booting up the PC when the upgrade installed. This program is included with the upgrade package on 3.5" and 5.25" diskettes along with easy to follow steps for installing the software onto your hard drive while running either DOS, OS/2 or Windows. The cache software will run each time the computer is booted an d since it simply turns the cache on it does not stay resident. It does not interfere with any operating system functions or applications the user will be running. 10) Easy Installation - Since the Cyrix 386 to 486 Upgrade Micro- processor solution is a single chip and there are no BIOS or other system modifications needed, installation is easy and straight forward. Installing the upgrade requires three steps: 1) Remove the 386DX microprocessor, 2) Insert the Cyrix Cx486DRx2 processor into the microprocessor socket and 3) Install the cache software. Difference between a 386 and a 486 Computers The viability of upgrading a 386 computer to a 486 by using the Upgrade Microprocessor can best be understood if we take a look at the real differences between the two types of systems: COMPONENT 386 COMPUTER 486 COMPUTER Microprocessor 386DX/SX 486DX/SX >>>>>>>>>> Supports 386 Supports 486 >>>>>>>>>> Instruction Set Instruction Set Graphics VGA Standard VGA Standard >>>>>>>>>> Super VGA Available Super VGA Available Disk Drive IDE Interface IDE Interface >>>>>>>>>> Multiple Drives Multiple Drives Memory SIMM Device SIMM Device >>>>>>>>>> Expandable to 12MB Expandable to 16MB From the above chart we can see that both 386 and 486 computers use VGA as the graphics standard, expandable SIMM memory, and an IDE drive interface supporting multiple drives. The major difference is the micro- processor. In the past, as each new generation of processor became available the only path for taking advantage of new processor technology was to pur- chase a new computer. This was true because of the major differences between 8088, 286 and 386 systems in terms of design, graphics, memory and disk interfaces. The key point with Cyrix's Cx486DRx2 Upgrade Microprocessor is that it upgrades the main difference between a 386 and 486 computer; the micro- processor. Compatibility The Cyrix Upgrade Microprocessor has been tested in numerous PCs for compatibility including systems from IBM, Compaq, AST, Everex, Dell and Toshiba. There have been only a few systems that have not tested compatible. The following systems have exhibited an incompatibility with Upgrade Microprocessor: - Sun i386 systems - Memorex 386 systems The IBM PS/2 Model 70/16MHz has tested compatible but the Upgrade Microprocessor requires the system to have 85ns memory installed. The system originally came from IBM standard with 2MB of 85ns memory. IBM's specifi- cation on additional memory called for 85ns memory. Unfortunately, a number of systems upgraded beyond the initial 2MB were upgrade with slower 100ns memory. Although this generally does not cause problems in the Model 70, when upgrading to a faster microprocessor the system will need all memory to be 85ns. This requirement only affects the 16MHz model. A small number of the early Compaq Deskpro 386/16MHz came with a 287 math coprocessor socket instead of the standard 386 math coprocessor. Installation of the Upgrade Microprocessor will require the removal of any 287 math coprocessor installed in the system. Packaging The Cyrix Upgrade Microprocessor comes in a single package containing th e following items: * Cx486DRx2 microprocessor chip * Installation Manual * Pair of 386DX microprocessor removal tools * Upgrade Cache installation disks (3.5" & 5.25") * Pin 1 locator arrow * * Heat sink (required for 20/40 and 25/50) * Warranty Registration Card * The pin 1 locator arrow aids in the ability of properly orienting the Upgrade Microprocessor correctly in the socket.