Upgrading 1.5 year old computer

[Zelpo]

Howdy folks

Running (what is now) an older system on XP OS:

P5B-E mobo
E6300 proc
EVGA 8800 GTS 320MB vid
Corsair XMS2 2x1 GB DDR2 ram
Seasonic 600w ps, Seagate 320GB HDD (7200rpm), Antec900 case (fans on medium)

Would like to upgrade while I can on current motherboard.
Note: I don't OC, but also not opposed to it. I'm just lazy and use the plug & pray method, hook stuff up and hope it works. Not much of a bios dabber, again not opposed (for example: bios updating)

I play Civ4 way more than I should, and this game is the limiter on my system. Can't play large maps as computer lags hard between turns. My goal is to play this game on any size map without issue/lag.

Okay, my thoughts and please pick this apart because I haven't kept up with the tech for the past year so I really don't know:

Proc
Probably my biggest limiter. Keeping the FSB the same speed as the Asus (1066), my options (for dual core, which I think Civ4 doens't even take advantage of but I do have multiple web pages, word docs etc up at any one time): E7400, or more speed: what's the advantage/disadvantage to running something like a E8600 which is faster but has a different FSB speed at 1333 ?

RAM
Dang that Corsair I use is on the cheap right now. Even though XP can't take advantage of a full 4GB, should I stick a couple more of these in just to get >3GB ?

Video card
I'm lost on this one. My head swims just trying to figure it out. I'm thinking ~$400 is my price range on this item. Suggestions?

Thanks for your time!

 

[enaher]

mmm... it depends if you will OC id get 2x2 pi GSkill Ram a C2D e7300 or e8400 and a Ati hd 4850

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231209 RAM 50$

http://www.newegg.com/Product/Product.aspx?Item=N82E16819115132 CPU 120$

http://www.newegg.com/Product/Product.aspx?Item=N82E16814102770 GPU 170$

Total 240$

that should be more than enough for Civ4

you could replace the e7300 for a 8400 and the HD 4850 for a 260GTX 216 and the total would be around 400$ and probably the best configuration with your budget. and might get higher Overclocks out of them.

 

[Proximon]

I play Civ4 a good bit.

Totally understood about the larger maps.

You may need to update your BIOS to run a Wolfdale CPU.

enaher has good suggestions. You do really need at least an E8400 if your board doesn't support 333Mhz FSB (It has nothing to do with the marketing number they provide of 1066) then you might need to grab a P43 or P45 board, which would be a decent $100 upgrade really.

So MB $100
CPU $170
RAM $50

Video card.... Well, to be honest I had pretty good performance from an 8800GT. You can get as much as you like of course. I upgraded to a Sapphire 4870 Toxic, but it wasn't for Civ.

I would have linked parts but newegg is having issues atm.

Here is some general advice:
http://www.tomshardware.com/forum/257075-31-what-parts-choose

And here is a list of links to good parts, including the video cards discussed:
http://www.tomshardware.com/forum/257547-31-personal-list-parts