You are talking two different technologies, here.
Here,..........pull up a chair, and let me explain.............
The Dell Dimension desktop computer's motherboard, has a different type of technology being used; than per se a motherboard which supports an Intel Core i processor.
Whether we are talking Intel Core i3, Core i5, Core i7, or Core i9.
The Dell's motherboard chipset, is composed of a Northbridge chip; and a Southbridge chip,
[Note* CPU stands for Central Processing Unit.
Another term used is Microprocessor, or simply Processor for short.
Does NOT mean PC. Personal Computer ]http://en.wikipedia.org/wiki/File:Motherboard_diagram.svg
The Northbridge chip handles the Faster capabilities of a computer.
Processor (CPU), Ram Memory, and HIGH-speed graphics.
[HIGH-speed graphics being the AGP technology, and the PCI Express technology.
Using a PCI graphics card in a PCI slot, is NOT high-speed graphics.
Using Integrated (OnBoard) Graphics, is NOT high-speed graphics ]
The Southbridge chip handles the Slower capabilities of a computer.
Anything connected to the;
1) PCI bus, and to include Integrated Graphics
2) IDE (PATA) bus
3) SATA bus
4) USB bus
6) Audio (Sound)
Motherboard's that support the Intel Core i processor's, do not utilize a Northbridge chip,http://www.hardwaresecrets.com/article/535http://www.hardwaresecrets.com/article/610http://en.wikipedia.org/wiki/Nehalem_%28microarchitecture%29
The Sandy Bridge micro-architecture was brought out to surpass the Nehalem micro-architecture,http://en.wikipedia.org/wiki/List_of_Intel_Core_i3_microprocessors
We are headed to the Skymont micro-architecture,http://en.wikipedia.org/wiki/Skymont_%28microarchitecture%29
Besides,........the processor socket you have on your motherboard is an LGA 775 processor socket.
The Intel Core i3 processors, use a completely different processor socket.
However, there are problems in architecture looming in the future;
Silicon will not have the capabilities for the newer processors.
(In about 10 years)
Talk is of going to Graphene.
Doesn't matter anyway.
In 10 years computing power will be so cheap, it will be the same as a sheet of wastepaper.
It will be in the wallpaper, your clothes, your toilet, and so on.
Our world will evolve exponentially.
(Unless some freak/s blo-w/s it up)
Computers will be as disposable as a sheet of paper.
Computer processing power follows Moore's Law.
Moore stated that processing power doubles every 18 months.
It is down to EVERY 11 months, NOW.
Seen the birthday cards that sing happy birthday to you?
The chip in the birthday card has more processing power, than all of the allied forces in 1945.
Your cellphone about the same power, or more; than was used in the first spaceflight to the Moon. (1969)
I wouldn't sweat it all that much.
Soon your cell phone will have more power, than that desktop computer you have has right now.
May be in contact lenses,http://www.youtube.com/watch?v=_UgE-NhcmbM
As for your Dell, once I find out the model number, we can see if it will support a better Intel processor, and more ram memory.
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