I'm a UI guy. If that doesn't make any sense to you, I can learn how to use almost any program, 20x faster then you can.
I can play, 20 games in a day, and switch between 20 different control schemes with out having to wrap my brain around how each of them work, or exam the 'manual' to remember. I can just load it up and play the game like I've been playing it all week.
Sometimes though, it may take me a few minutes (upwards of 5) to exactly remember every fine detail point of the control scheme, or how the UI works. Buts its like riding a biscycle. Even after 20 years of not riding a bike, once you hop on it, you remember the fundementals, and the first few pushes on the pedals will be a bit akward, but after, you'll ride like a pro again.
Then approximately 4 years ago, I installed my first Video Card.
Then my first Ram.
3 years ago, I desemebled my pc, to send my motherboard in for an RMA.
Had a friend who built the pc orginally come over and put it back together.
This summer I finally built my first computer.
To be technical, my first 'build' was just re-esembling a pc after replacing a bad mobo.
Then I technically assembled my first computer, the one I'm using now.
Q6600 2.4ghz
Geforce 9800 GTX
PC 6400 Memory
2 300 GB HDDs, and who gives a frag at what speed.
Crossair 750W PSU
And a bunch of other accessories.
Originally at $600 (Dell would have charged you somewhere around $2400 for this build at around June, I know, I tried building it through dell but my credit wasn't good enough!! So I put all the parts I needed on my credit card and paid it all off in under a month.

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The price jumped from $600 though when I had to invest in a new PSU (Got a bad one, to tiny for the video card, EVERYONE missed that thing, cause you always, always ask around when its your 'first time' if 'this part' will work with 'that part', ect. Its called research people! If you don't know how to rebuild an engine, don't just start throwing pieces together and try to mash em together with ducttape if they dont' fit!

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AS for basic computer problems, 99% of all problems you have on your PC, are spyware related, and 99% of the time, someones already had the same problem you have had. A quick 'google' of your problem often yields a solution.
If more people would actually RESEARCH there problem before turning of there brain and hitting there pc with a wrench because its to powerful for there monkey brains to handle, We'd have sooo much less whining going on!
As for cars. I suck at cars. About all I can do is change tires, change oil, check oil, you know the basic fluids that are at the top of the engine unless you have one of those cars that hides all that shit in really wierd places, or like my parents car, where you have to take half of it apart to put new fluid in...