Jeff, some of the system's ram memory is being borrowed. If you are using Integrated Graphics, this is where it is going.
[Integrated Graphics is also known as OnBoard Graphics.
On the motherBoard.
The GPU is soldered to the motherboard. (Hence you plug the monitor cable into the motherboard, via a VGA connector,http://en.wikipedia.org/wiki/VGA_connector
A dedicated graphics (adapter) card has it's own GPU.
(Graphics Processing Unit,http://en.wikipedia.org/wiki/GPU
Integrated Graphics uses some of the system's resources. The Processor, and Ram Memory.
A dedicated graphics card has it's own Processor, and Ram Memory.
(GPU, and graphics ram memory)
PC2100 is DDR Sdram that operates at a frequency rate of 266MHz.
PC2700 is DDR Sdram that operates at a frequency rate of 333MHz.http://en.wikipedia.org/wiki/DDR_SDRAM
Proper 'computer speak' for Speed.
'Speed' is slang.
Double Data Rate Sdram
Synchronous Dynamic Random Access Memory
Mega = Approximately 1 Million
Hertz stands for Cycles per Second.
PC2100 can operate Up To a frequency rate of 266 Million Cycles per Second.
PC2700 - 333 Million Cycles per Second ]
No, using PC2100 is going backwards, and will not help increase the Amount of ram memory, seen by the computer.
According to eMachines Support, the T2642 desktop computer's motherboard, uses an Intel 845GV motherboard chipset.http://www.emachines.com/support/product_support.html?cat=Desktops&subcat=T%20Series&model=T2642
[Chipset, and Chip are slang terms for I.C.
The motherboard chipset used for the technology of the T2642 motherboard, is the Northbridge, and Southbridge chipset.
(Motherboard's for the Intel Core i3, i5, and i7, do not use this motherboard chipset technology)http://en.wikipedia.org/wiki/File:Motherboard_diagram.svg
(CPU = Central Processing Unit. Another term used is Microprocessor, or simply Processor for short.
Memory Slots = Ram Memory slots ]
The Northbridge chip handles the faster processes of the computer.
The Processor, Ram Memory, and high speed graphics.
High speed graphics being AGP, or PCI Express.
Not a graphics card inserted into a PCI slot.
Integrated Graphics, or a graphics card inserted into a PCI slot, is a slower process of the computer.
Slower processes of the computer are handled by the Southbridge chip.
(At the end of the Northbridge article's first sentence, you will see - southbridge, in blue.
Left-click on it for more info on the Southbridge)
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