Memory - Upgrading and Repairing PCs - page 406

board and chipset speeds, you won't see an advantage to using them unless you are over-
clocking your system and your motherboard supports the corresponding overclocked pro-
cessorandmemorysettingsthatthesemodulesrequire.Inaddition,becausethesemodules
usestandard-speedchipsthatarerunningoverclocked,theyalmostalwaysrequirecustom
voltage settings that are higher than the 1.5V that standard DDR3 memory uses. For sys-
tem stability, I generally don't recommend using overclocked (higher voltage) memory,
instead preferring to use only that which runs on the DDR3 standard 1.5V.
Table 6.10 Overclocked (Non-JEDEC) DDR3 Module (240-Pin DIMM) Speeds and Transfer Rates
Typically, you can find DDR3 modules rated CL 5 through 10.
RDRAM
Rambus DRAM (RDRAM) was a proprietary (non-JEDEC) memory technology found
mainly in certain Intel-based Pentium III and 4 systems from 2000 through 2002. Very
few of these systems are still in use today.
For more information about RDRAM and RIMM modules, see Chapter 6 , “ Memory ,” in
Upgrading and Repairing PCs, 19th edition .
Memory Modules
Originally, PCs had memory installed via individual chips. They are often referred to as
dual inline package (DIP) chips because of their physical designs. The original IBM XT
and AT systems had 36 sockets on the motherboard for these individual chips—and more
sockets could often be found on memory cards plugged into the bus slots. I remember
spending hours populating boards with these chips, which was a tedious job.