I was actually gonna advise you, but took a look through the previous posts and decided the bases were covered, Sound advice in this thread, and a super article from captainHaplo-- Credits awarded for the time input bro!!
I'll Just hammer home a couple of points-
Wattage WATTage And WATTAGE!!!!!!!
And i would disagree with point made bout not needing the extra ram on your graphics card-- quite simply get a card with as much as you can--- Oh and i do this for a living-- computer engineering that is, not subsim posting :D

Well I upgraded to a new computer (self built) when this game come out but didn't want to spend much over $500 us.

AMD X2 4600 dual core 2.4ghz processor
Gigagyte GA-M55SLI-S4 motherboard
Gskill 2x1024mhz memory in Dual Channel
Evga 7900GS KO Pci-express video card (550/1380mhz)
550 watt (38amps) dual 12v rail power supply

Runs SH4 with max settings and no stutter......

On the box for my video card it says 450w power supply minimum.

You know... how hard is it to build a computer? I mean I replaced my CPU last year myself. In terms of the right drive connecting to the motherboard the right way I've never tried.

It's just that I could save so much money if I were to build it myself.

I wonder if I could do it and not end up shooting myself in the foot.

Replacing a CPU properly is, by far, the most complicated operation in the construction of a PC. If you can do that, the rest of it is cake.

(Hint: most modern drives are 'Serial ATA' - it doesn't really matter what you plug in where, as the cables all run from the SATA port on the mobo straight to a drive. I suppose you want to find the SATA 1 to connect to your main disk, but...that's it. And the rest of it's nothing at all - just plugging connectors together and putting cards in slots.)

What about attaching the motherboard to the case? How do I know it will, well, connect or are they, standardized?

How does a AMD Athlon 64 X2 5400+ 2.80GHz / 1MB Cache / 1000MHz (2000 MT/s) / Windsor / Dual Core / OEM / Socket AM2 / Processor compare to the Intel Dual core E6600 2.40 GHZ processor?

I'll tell ya. If you haven't built a system recently, you might want to try one of these build guides. Ars has a great one here with lots of options for most budgets and they always find the best quality/spec'ed parts for that configuration. Of course, you can remove parts you already have for considerable savings (like monitor, keyboard, etc.) . The good thing about this if you a new to it is that they spec the best parts for the money, giving you the exact parts and brands, plus the price of each. I'd say the core components on the 'God Box' in this guide would rock this game:

http://arstechnica.com/guides/buyer/guide-200706.ars

That's the exact vid card I'm using and my processor isn't near as fast as the E6600. I can play with the graphics cranked up all the way and get 30fps easy with the 7900GS. It's very affordable for the performance too.:rock:

It's a tad slower but will save you money. I'll probably be sticking with the AMDs just to save a few bucks for maybe 2% less performance on certain things.

Clock-for-clock, AMD's Socket AM2 offerings are about 20% slower than Intel. So a 2.8ghz AM2 would run vaguely like a 2.2ghz Core 2 Duo. AMD's '6000+', at 3.0ghz, is largely considered bang-on equal to the 2.4ghz E6600. Which is good, as they are basically the same price. And so it goes...

(This is actually something good to consider - I know many bought top-end AMD systems back when Socket 939 was king, and felt largely crushed by Intel's Core 2 superiority in benchmarks. While it's certainly true that nothing from AMD can touch a quad-core 3.0ghz processor, a LOT of AMD's chips are still very competitive, especially for the price. For example, while being "old school" Socket 939, my 2.3ghz AMD proc is actually as fast as either the Core 2 Duo E4300 and E4400 at stock...and given that 'upgrading' to an E4400 system would run something like $500...)

Buy a Tuniq Tower 120 so you can OC the hell out of it. I got my E6600 to 3.6 GHz before blowing up a pair of $300 G.Skill RAM chips, and that was with a lousy 1200 RPM fan on the CPU. I got some OCZ Plat Rev.2 and they're rock solid. I've settled down at 3.0 GHz which is good enough for now, given how expensive all this was.

I'd recommend an 8800 GTS 320 MB video card if you can afford it and don't mind some driver issues. If you're not a tinkerer and are afraid of any problems, just get the most expensive 7900GT that you can.

Get a SLI compatible motherboard, maybe the NVidia 680i chipset if you can, or the cheaper 650i. If you're adventurous you can find some Intel 975X boards that can be modded to do SLI.

Xander is absolutely right.

If you don't want to blow the money on the highest-end hardware you can get, grab an AMD. It'll usually save you money, though the processor war goes back and forth. I'll stick with the underdog small company all things being equal. ;)

Besides, I've been a bit put off with Intel's socket LGA 775 lately. Mounting the heat sink/fan on them can be a real pain in the ass even though I like how they put the pins on the motherboard. Still, I like how easy it is locking down an AMD setup over the current Intel one much better. I fingered a few Intel 775s in the past year or so and I haven't been impressed in the least with putting that processor cooler on. For example, if you wanna upgrade your Intel cooler to a good one, you'll generally have to take your whole motherboard out since the good coolers require you to put plates on the back of the motherboard. BS.

The AM2 line isnt quite dead even per clock cycle with the Dual Core Intel chips - but they have improved from the first X2 lines. Honestly - your not going to be hitting a cpu bottleneck with either AMD or Intel at the price point your looking at. Since the performance is close at price (not clock speed) - I would let the deciding factor be what vid card you choose. AMD and ATI - or Intel and Nvidia. Any performance you might lose in the initial choice is gonna be made back up if you match partners.... Of course - you mentioned upgrading - so that has to be in your mind as well - although true dual core apps (and games) really arent out yet so Quad-core optimizing is WAY off time wise.... I wouldnt worry with it personally.

Someone made a mention of overclocking. Since this is going to be your first build apparently - DONT EVEN THINK ABOUT OC'ing! Its great once you know how - but you do it wrong and you fry a 200 buck vid card that the maker wont warranty cuz you mucked it up and you wont be a happy camper! Nuff said...

As for mb's - they have standard sizes. If you have a full size "desktop" tower, then any ATX, Mini ATX or Micro ATX board will fix. Again - for simplicity sake - go standard ATX - its a bigger board - meaning you have more room to get in there and get everything plugged in right. Plus you get more slots for upgrading later as needed. Installing the board isnt an issue - just some small screws (with gasket) that hold it to the case (usually 6). Most boards today are grounded to the case thru the "backplate" (as well as the screws) that snaps in where all the ports are in the back of the box. Its easier to put the CPU and fan onto the MB before you install the board - then once its in you just have to hook up all the cables and cards. Cards are easy - you have probably done em before. Just insert and apply even force until it seats - then run in the frame screw. Memory - same even force till both latches seat on the DIMM. Then you have power cables from the power supply, they go to MB, drives, and occasionally the vid card or other addin, as well as case fans and such. Once thats done, you hook up the power, reset and LED lights from the case to the MB, USB front connectors if you got em, and your usually good to go. Occasionally a MB may have a jumper or 2 you have to move on the board itself - but thats it. Boot - go to bios and start getting setup.

If during boot there is a problem - the number, pitch and duration of the beeps will tell you whats wrong. For instance - warbling means memory isnt seated right. A constant chirp is video... etc. POST is a great tool when things dont work the first time. From there - make sure all your drives are detected - and if so - you just built yourself a PC - now install an OS on your Hard drive - (the lovely process known as a REBUILD!), get SH4 on it - patch, mod and play - then let us know how it goes!

If you need any more input - ask away - we all will help as we can.