how to replace motherboard and pwr supply- where to look?

I am thinking of replacing the motherboard and pwr supply in my dell dimension 4550.
I want to know what facts do I need to know about the motherboard and pwr supply to purchase new ones? and where to look - in the software or do I have to actually look at hard ware to find serial numbers or whatever i need?
Thank you
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Rob SiddellCommunity Educator IICommented:
I would contact Dell Tech support to help you find the right part numbers for replacing them. All you will need for them is your Service Tag located on the computer case.
Rob SiddellCommunity Educator IICommented:
you can either call them or chat with them online at

I would suggest chatting online as it can be difficult to understand some of the thick accents so there is less room for confusion on both ends.

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