No, it's a terrible ORdeal. Fist thing is, you will usually have to ALSO buy a case and power supply. Now you MIGHT be able to find some cheap garbage case, but hey, if you have a Dell, you probably have the Dell version of the $80 Palo Alto case, you certainly don't want to DOWNgrade.
Then if you don't really want to waste that fast CPU, you'll want DDR SDRAM, so even though you can upgrade without DDR, doing so would add more money to the cost of the system.
Finally, you have a system with a System Restore CD. It won't work with the new board. So now you have to buy an OPERATING SYSTEM and any other software you already have that you want to keep.
And say you have an ISA modem, a nice one, maybe some ultra expensive USR modem. You'll have to replace that too, if your new board has no ISA slots.
So in the end, for the majority of people with OEM systems, they're better off upgrading the CPU, or else selling the whole system and buying a whole new system. The motherboard upgrade is not a good option.
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