Some of these items were at unusual sale prices, but anyone could come within $100 of this system price without even shopping.
This system loads MS Word in under half a second. The need for all the memory comes from heavy Photoshop use.
I seldom upgrade older computers, except to add memory. They can be sold or given to friends or relatives or schools.
The reason you need a new motherboard is to recognise all the new hardware, to get USB 2.0, to enable use of ATA100 drives, etc. You can get a great AMD motherboard, CPU and 512 megs memory for under $250.