re: heavy-duty graphics work
I do build them myself, and I do spend thousands of dollars. I don't scrimp on the equipment. For example, just my 450W power supply was from PC Power and Cooling, and was $230. Next system may have a kilowatt unit, and that will run almost $500.
I make my living on this stuff. Payoff is that I have never had a major mechanical failure, and I run this thing in a garage.
Doesn't mean anything's wrong with the low-cost approach, it may be I'm just more belt-and-suspenders than most people.