User manual SONY VAIO VPC-EA2VFX

[. . . ] Throughout the history of the PC, memory technology has steadily progressed in capacity and performance to meet the increasing requirements of other PC hardware subsystems and software. In the past, there have been relatively clear industry transitions from one memory technology to its successor. However, today there are multiple choices in memory technology, such as the PC133, RDRAM, and Double Data Rate (DDR) processors. The road map, as shown in Table 1, offers an overview of the evolution of memory. Table 1. [. . . ] The DDR memory module is suitable for virtually every segment of the PC market that includes the workstations, and high-performance, low-cost desktops. The DDR module offers the following benefits: · · · excellent performance high capacity/density expected high-availability at a low cost How does DDR differ from RDRAM and SDRAM? So what's so new about the DDR module?The physical dimensions of a DDR memory module are identical to those of a standard DIMM -- the same length, same pin pitch (spacing), same PCB thickness, and so forth. The difference in the module is in the channel. A standard SDRAM, now referred to as Single Data Rate or SDR, module has two keys, or notches, where there are no pins. The DDR DIMM module has only one key because it packs 16 extra pins into the space of the second channel. Therefore, the DDR module has 184 pins compared to the 168-pin SDRAM module. The new 184-pin module adds new strobes, clocks, and power and ground signals. A key factor in the pin changes means that no existing 168-pin SDRAM module will work in a 184-pin DDR motherboard. Reliability and Value of Purchasing Compaq Double Data Rate Memory White Paper 4 A DDR module has the same number of pins as a 184-pin RDRAM module, however, that is where the similarities end. The two modules are keyed differently, have different pin pitch, and completely different architecture. Table 2 provides a comparison of the pin count of the SDR, RDRAM, and the DDR processors. Table 2. No other reseller has the resources to conduct such extensive testing on Compaq equipment. · · Reliability and Value of Purchasing Compaq Double Data Rate Memory White Paper 7 · Impact of Memory on System Warranty -- Compaq's superior testing and certification procedures allow Compaq to offer a three-year pre-failure warranty on Compaq memory, drives, and processors. 1 The Compaq warranty does not cover service or parts damage resulting from the use of non-Compaq brand memory. Only Compaq brand memory has been extensively tested and certified for use in Compaq Desktops and Workstations. Price and Value -- Although Compaq memory is thought of as being more expensive than other memory modules, price is relative to the value of the product. Avoiding system downtime or data loss caused by memory failure and the financial impact such situations cause far outweighs the momentary benefit of paying less for the initial purchase of memory. Single Supplier Convenience ­ Compaq offers everything customers need for Compaq systems and verifies that all of these components work together, ensuring the quality of all of its products from beginning to end. · · Summary So why buy Compaq memory?The main reasons a Compaq customer should buy Compaq-branded memory are: · · · · The assurance you have the highest quality memory made. The reassurance that your memory is qualified and rigorously tested to work on your Desktop and Workstations. The peace of mind a Compaq warranty can provide you. Only Compaq has the facilities and the procedures to test, verify, and certify memory to Compaq standards. 1 Certain conditions exist. . Call 1-800-OK COMPAQ for more information. Reliability and Value of Purchasing Compaq Double Data Rate Memory White Paper 8 Appendix A Table 4. Compaq versus Other Memory Resellers Compaq Memory Qualification Procedures Prior to purchasing memory modules from a DIMM manufacturer, Compaq qualifies the manufacturer's module design and manufacturing processes. [. . . ] In addition to the rigorous testing manufacturers are required to conduct according to the Compaq qualification procedures, Compaq performs additional testing of the memory modules as follows: · Every module placed in a desktop or workstation for shipment goes through run-in testing. · A Product Integrity Audit (PIA) is conducted on all memory modules going into option kits. These testings allow Compaq to ensure that every module branded a Compaq memory module has passed an extensive series of tests ensuring quality and reliability in all Compaq desktops and workstations. Due to the superior testing and certification procedures, Compaq is able to offer a three-year prefailure warranty on Compaq memory, drives, and processors. [. . . ]