HP Vectra VE 5/xxx HP Vectra VE 5/xx Series 2, Familiarization guide - Page 11

1 Product Overview and Features Product Features Microprocessor Cache Memory Main Memory NOTE The Pentium microprocessors used in the HP Vectra VE 5/xx series 2 use internal clock multiplication, similar to that used by the 486 DX2 processor. The microprocessor's internal clock is a multiple of the system clock. The Pentium 75 MHz and 100 MHz processors multiply the 50 MHz and 66 MHz system clock by a factor of 1.5. The Pentium 133 MHz processor doubles the 66 MHz system clock. The Pentium 150 MHz processor multiplies the 60 MHz system clock by a factor of 2.5. To set the appropriate switches for each processor speed, refer to the Pentium Processor table in the section System Board Switches in chapter 2. The system board of the HP Vectra VE 5/xx series 2 has a Voltage Regulator Module (VRM) which supplies the Pentium processor with the correct voltage. The VRM allows the processor to be upgraded without replacing the system board. The 75 MHz, 90 MHz, 100 MHz, 133 MHz, 150 MHz and 166 MHz processors need a passive shortening block VRM (providing VCC voltage). The appropriate VRM is provided with each processor upgrade kit. The microprocessor has two 8 KB first-level cache memories: one for instruction codes and the other for data. The HP Vectra VE 5/xx series 2 PC has a socket for a 256 KB second-level cache memory module. There are two modules available, a 256 KB asynchronous cache memory module (D4049A) or a 256 KB synchronous cache memory module (D3659A). When the optional second level cache is not installed, the cache socket protector must be installed in the empty cache. The role of the cache socket protector is to properly terminate the Pentium host bus. The HP Vectra VE 5/xx series 2 PC has six DRAM (Dynamic Random Access Memory) sockets on the system board. The PC uses 60ns, 32-bit wide, EDO memory modules. 8 MB (two 4 MB modules) or 16 MB (two 8 MB modules) of memory is supplied as standard, expandable to 128 MB. Memory modules must be installed in pairs of identical modules. Install only 4 MB or 16 MB modules in bank C. Bank C supports only single density memory modules. 7