Need help, what does OCing do, do I need it for gaming?

[clutchstrike]

The reason I label myself as an idiot is because of this. I spent a good two weeks building a theoretical overclocking computer (adding to newegg wishlist). Now I realize, I don't even know what overclocking does. It raises the clock speed, but what does that do? I have to ask myself what do I want in a PC? Right now, the most I can ask of a PC performance wise is to be able to play Half Life 2 on max settings, be able to alt tab and switch between programs (iTunes, AIM, internet) with no delay (what I have now.) But then I have to think, what about games in the future, so I also have to prepare for that.

This is the production of those two weeks I spent:
Intel C2D E6400
Gigabyte DS3 Mobo
2GB G. Skill DDR2 PC800 6400 RAM
eVga GeForce 7600gt
7200.10 seagate 250 gb HD
Hiper 580W PSU
Cooler Master Centurion Case
Arctic Cooler 7 Pro

Then now I realize, I need to splurge on the graphics card, but still, I have no idea what overclocking does, and how it will help me in my future endeavors. So... do I want to keep this build, or not?

Any help is appreciated guys.

 

[WR2]

Overclocking your CPU will make your $220 CPU perform about the same (or better) than a $950 CPU. Speed for free.

 

[WR2]

What video resolution do you use for gaming? 1280x1024?
In your proposed system I'd guess that the gaming performance bottleneck (limiting factor) will be the 7600GT video card.

Overclocking your E6400 won't have as much a performance boost as going from a 7600GT to a 7900GS or 7900GT. I think you can find a 7900GS for about $60 more than than a 7600GT.

On the other hand if you're interested in waiting for the newer high end (8800GTX 8800GTS) DX10 cards to drop in price or the mainstream DX cards to appear in the new year (8600 series) then a 7600GT isnt a bad interim video card.

 

[clutchstrike]

How is this build? (No overclocking)


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[WR2]

You still have the E6400 and GIGABYTE GA-965P-S3 motherboard which is a good overclocking combo.
What is the price difference between the RAM in ver 1 and ver 2?

 

[clutchstrike]

$9.

 

[WR2]

I'd say spend the $9 and get the GSkill DDR2 800 RAM.
If your budget will stretch for the 7900GS it is a pretty good upgrade from the 7600GT. If you're looking at any of the DX10 games coming in the next year (Crysis?) and want a DX10 card in six-nine months or so I'd say stick with the 7600GT for an interim solution.
Have you checked the HL2 forums for info on the upcoming Episode2? You should be able to get a good feel for which card would best suit your needs.