gonna say at the beginning, this is a post disagreeing with Latios. it's nothing personal, just my opinion differs. also, this is kinda branching off topic from the uses Emperor Zap listed as needing the new computer for.
Latios said:
A workstation is a general purpose computer.
The minimum price for the complete set (Tower and Monitor) should be around $1250 unless there's a sale. But always have $1500 if you're going for this type.
I'm going to have to disagree. if you pay more than $600 (including the 15" LCD) for a workstation, you're either getting ripped off or are the victim of marketing. the majority of the general public will be perfectly happy and should get good multiple years use out of a $600 workstation.
I won't touch media center boxes, but i'm going to break your "gaming machines" into 2 different types. into your top-of-the-line (probably a little above what you listed) and your lower solid-gaming-machine. you're custom, top-of-the-line are generally bought by people who want the best of everything currently available in their machine. generally, they're people with more money than sense. this type of people pay two or three times as much to get that extra 10-20% performance boost the "very newest" gives.
PCI Express:
PCIe is the future, but as of right now, there is almost nothing that can take advantage of it. I would guess i'll be another year or two even before the stuff that can take advantage of it is reasonably priced too. I wouldn't worry about getting a board with PCIe unless you could get a one by only paying a little above what the non-PCIe board would cost.
AGP/Video card:
Personally I would not consider a board without a AGP slot. onboard video is fine for an amazing amount of the games currently out, but get a mother-board with AGP so later on if you find yourself wanting better looking graphics, or your game requires higher end, you can just buy yourself a nice AGP graphics card and stick in.
like Latios said, GeForce .vs. Radeon is personal opinion. different games cater to different cards (depending on who was willing to sponsor the game makers). generally you'll get the best performance .vs. price from about a $150-$200 card, although I have a very low end GeForce FX 5200 (seen them for as low as $35 after rebates), and I can play the new counter-strike:source (been out about a month) very well with all my graphics settings on highest and my anti-aliasing on 2x.
CPU:
for gaming, yes, celeron isn't the best. however, it is generally about half the price (or less) than a P4 would cost. also, 64bit is cool, and very likely the future, but again there is almost nothing on windows software-wise that can take advantage of true 64 bit and it will be a while before that changes. and in the mean time, 32bit hardware will be supported for MANY years to come.
with a Pentium 4, 3.4ghz would be the absolute highest I would go. your boxed 3.0ghz and 3.2ghz can be had for almost half 3.6ghz price and generally offer the most bang for the buck. the Pentium Extreme chips are a total joke and I would absolutely stay away unless you're so deep into the "more money then sense" you can't see out anymore.
RAM:
I too have to be careful here, but 512 is usually enough RAM for even most gamers, and over 1gb is a waste unless you're editing obscenely large files or running something like a server with hundreds of threads running simultaneously. and I would currently avoid DDR2 memory if you can because it's currently a lot more $$ for minimum amount of performance gain.
Harddrive:
if all you're doing is running programs from it, you'll probably never fill a 40gb. and when you want to start storing music, movies, tv episodes, whatever, a second drive is insanely cheap if you watch rebates (friday after thanksgiving, several places had 200gb drives for < $50 after rebates. where-as if you buy them with a computer, you'll pay many many times more)
floppies, CD/DVDs etc:
floppy drives are useless. spend the extra $15-$20 they'll charge you for one and buy yourself a USB flash-drive (aka keychain drive, aka pendrive, aka jumpdrive, aka hundred other names). the 128mb and even 256mb are dirt cheap and even the larger (512, 1gb) ones are fast becoming reasonably priced. flash drives easily hold 100x or more info than a floppy, and it won't get corrupt if you breath on it wrong. only get a floppy if you have a ton of old floppy disks you still need data off of for some reason.
what CD-rw/dvd player, dvd burner, is a completely personal choice. will say from experience, amazing amount of people get a dvd burner (or player) then never use it. but they're also a very easy add-on you can get later and stick in.
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anyway, all that said, i've fallen into the "more money than sense" before and bought myself a $3600 computer about 5 years ago. probably the worst mistake i ever made. now i have a nice heavy $3.6k paperweight... where-as if I'd have bought myself a good solid $1k desktop, and could have replaced it three times by now and made various upgrade and still spend the same amount of money. Each time I would have been able to play all the latest games with each machine (and been able to play newest games for a year or two into the future), then when it gets to slow, resold it for a couple hundred and bought a new one.
I'd much rather spend $1k and get a solid machine good for 2 years (then replace) then spend $3.6k and get a top-of-the-line machine good for 3 years. you can resell the old machine, pass it on to siblings, turn it into a server, donate it for tax credit, scrap it for parts, whatever.... and you'll still come out ahead in the long run and have the bonus of not being screwed when you buy something like RAMBUS memory, or super-disks, or 100 other things because it was going to be "the next best thing" when you bought your machine.
