The last PC I built was in 2003, so bear with me.

I'm working from scratch except for the videocard which is a Radeon 9700 Pro, so I need and AGP 8x compatible mobo. I would Ideally like to spend up to 400 dollars on the components I need. I am willing to spend up to 500 only if the performance increase is exceptional.

I am in for gaming, but I am not very worried about maximizing performance. WoW and Civ IV should run very well. I don't play much else, but I have decided I want an Athlon rather than a Sempron - otherwise I am willing to sacrifice a lot of shiny for a good price. I also use photoshop with a tablet and need to burn DVDs.

I built two rigs on newegg to my specs, a <400$ and a <500$ rig, both using the same HD/RAM/DVD-RW Drive, one socket 939 one a micro-atx 754.
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ATX Socket 939 vs. Micro ATX Socket 754
939 Case : JUST PC Black Steel ATX Mid Tower Computer Case 420W Power Supply - $29.99
939 Mobo : Gigabyte GA-K8U-939 Socket 939 ULi M1689 ATX AMD Motherboard - $58.00
939 CPU : AMD Athlon 64 3700+ San Diego 1GHz FSB Socket 939 - $223.00
939 Total : $311

754 Case : Foxconn 3GTW-01 Black/Silver Steel MicroATX Mini Tower w/ 300W Power Supply - $35.99
754 Mobo : ECS 760GX-M Socket 754 SiS 760 GX Micro ATX AMD Motherboard - $49.99
754 CPU : AMD Athlon 64 3000+ Venice 800MHz FSB Socket 754 E6 - $125.00
754 Total : $211

Other Components
Optical Drive : LITE-ON Black ATAPI/E-IDE DVD Burner Model SHW-160P6S - $42.99
HDD : Seagate Barracuda 7200.7 80GB 7200 RPM IDE Ultra ATA100 - OEM - $55.50
RAM : CORSAIR ValueSelect 1GB (2 x 512MB) 184-Pin DDR SDRAM DDR 400 (PC 3200) Unbuffered Dual Channel - $81.00
Video Card : ATI Radeon 9700 Pro AGP 8x- I own this already
Total: $180

Total rig 754: $391
Total rig 939: $491
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I have an extra 350w power supply of decent quality in case the ones that come in the cases aren't good. (The JUST PC case's PSU I'm especially suspect of). Other than that, I'm a little in the dark.

The Black aesthetic isn't mandatory, it just seemed to happen.

I'm not sure what the performance difference between the Venice and the San Diego is worth; Is it worth an extra 100 dollars? Any other strategies for high performance-for-price improvements on the rig?

Opinions/suggestions greatly appreciated

Links to the wishlists on Newegg:
754 Rig :
http://secure.newegg.com/NewVersio [...] cket%20754

939 Rig :
http://secure.newegg.com/NewVersio [...] cket%20939

**Edit
Thanks mdd19763 for pointing out I had DDR2 memory.. fixed now (the low cost had tricked me)

Note:

You can not use DDR2, any socket 754 or 939 MB needs plain ole 184 pin /DDR PC3200...

You might want to see if you can get a socket 939 NForce3 board, as they are AGP and excellent performers, being nearly as fast as todays NF4 boards....

If the jump to NF3/939 is too steep, then the socket 754 rig will do nicely...pick whichever processor is in your budget range, although I'd prefer something 3400+ and above...

Thanks for the advice, though NForce3 boards for 939 on newegg are scarce and about 35-45$ more. Is the ULi M1689 chipset not very good/generic?

As far as the 754 processors, what is the comparison between:
AMD Athlon 64 3000+ Venice 800MHz FSB Socket 754 - $125.00
AMD Sempron 64 3400+ Palermo 800MHz FSB Socket 754 - $123.00
AMD Athlon 64 3400+ Newcastle 800MHz FSB 512KB L2 Cache Socket 754 Processor - OEM - $165.00 ($195, +30 or so for CPU Fan)
AMD Athlon 64 3400+ ClawHammer 800MHz FSB 1MB L2 Cache Socket 754 Processor - OEM - $179.00 ($209, +30 or so for CPU Fan)

The only difference between the 3000+ Venice and the 3400+ Palermo seems to be the Venice's 512mb over Palermo's 256, which is worth the 2$.
The 3400+ Newcastle/Clawhammer, after the CPU fan(They're only available from Newegg OEM) represent $75/$90 dollar increase in cost with a 30 dollar fan. The Clawhammer is .2 Ghz slower than the Newcastle with double the L2 cache, which is cool but i'm not sure is necessary for me.
First, is the performance from 3000+ Venice to 3400+ Newcastle a big difference? It seems to me the only differences are +.4GHz, and a form factor of 90nm vs 0.13 µm (Which might be irrelevant). Is 75 dollars worth the increase in GHz alone, or do Newcastles offer a marked advantage in architecture?

I appreciate your advice; it looks like the 754 processors jump in price after 3000+. As for my RAM mistake, I've fixed it, thank you!

**Edit: Typo

what you want is definitely the 3000+ and OC it. some cheap mobo like the one you picked, or the ASROCK 939 Dual-SATAII with both PCI-e and AGP for future upgrade.

Some cheap Patriot signature RAm at 1gig (2x512mb) for $80 shipped.

THe Uli chipsets rock the NF4 in price and has way better sounds, but unfortunately not the ULi you picked. Why do you think nVidia bought them? Cuz Uli is causing them headache by making cheap, good chips for ATi.

The Clawhammer and Newcastle are not worth the $$$, cuz they don't do dual-channel DDR, which means slower ( alot slower) performance.

If you buy anything buy a 939 socket. This motherboard allows you to upgrade you video card later as well as you processor. Also change your hard drive to SATA II to utilize a more modern interface.

$54 ENERMAX Pandora CA3030-BS Black/Silver 0.6mm SECC ATX Mid Tower Computer Case Power UP 400W 24Pin Power Supply

$66.99 ASRock 939Dual-SATA2 Socket 939 ULi M1695 ATX AMD Motherboard

$160.00 AMD Athlon 64 3200+ Venice 1GHz FSB 512KB L2 Cache Socket 939 Processor

$81.00 CORSAIR ValueSelect 1GB (2 x 512MB) 184-Pin DDR SDRAM Unbuffered DDR 400 (PC 3200)

$41.99 LITE-ON Black 16X DVD+R 8X DVD+RW 8X DVD+R DL 16X DVD-R 6X DVD-RW 16X DVD-ROM

$63.00 Seagate Barracuda 7200.9 ST3808110AS 80GB 7200 RPM 8MB Cache SATA 3.0Gb/s Hard Drive

$466.98 Total this not only leave you an upgrade path you can use your existing video card.

some more $$$ saving stuff

Ultra Wizard UV case for $31.55 shipped from www.thenerds.net

Patriot 1gb signature PC3200 $77.99 from newegg

WD 80gb caviar 8mb cache 7200 rpm $55 shipped from www.techforless.com

that saves $20 toward a new video card. Make sure you use www.pricegrabber.com for low prices. But check the vendor rating first.

Dang man are you trying to stay behind in the computer world? The budget pc your building will be out in a few months. Get some CC and build a little better one. I mean at least about 300 bucks more. What do you want to use it for? Gaming or just browsing the net?

I think you better off doing a bit more researching before you decide on the products. I mean newegg is a good place to start but they are no longer the best in the business. What do I mean by that? Well to start off, no one wants to pay shipping for every product they order. No one. I am certainly one of them. You better off going to pricewatch and search for the best possible price and save the most money. Besides, you are in a very strict budget am I right?

My suggestion is this:
1. Skip off AGP motherboard altogether. With the recent addition of Nvidia Geforce 6100/6150 chipset, you do not need to shell out extra money to get an advance motherboard but you can't use it because you're short of cash to get the video card appropriate for the board. You can save that money and buy it later. Goggle it and you can find that Biostar 6100 is much affordable and you can OC'ed it better than similar board twice more expensive.
2. Skip off Venice core and get Opteron 144/146 instead. Why? (a) They're similar in pricing yet (b) has 1MB L2 Cache (compared to 512K for Venice) and (c) build for server/high end workstation so it can withstand heat in overclocking better than the regular retail stuff.
3. Buy your harddrive retail. Why? Because when you buy retail with rebates you'll ended up with a cheaper harddrive than buying OEM or online. Sometimes, for the same amount, you can buy HD four times the capacity of the drive you have right now. That is especially true when you live close to Fry's Electronics. Just make sure you don't buy the one that has been opened before.
4. Corsair Value Select is okay but not when you want to go gaming. I'm sure divider would help speed up the computer a bit but if the next better performing chip is ten or twenty more bucks, GRAB IT!
5. Are you sure you know your computer? Never follow what Vascular recommends. He needs to learn that Regular ATX board DOES NOT FIT Micro ATX Chassis. Lucky you, however, the Geforce 6100/6150 are all MicroATX. That means you can save some space by not putting the computer on the floor. Cooler Master RC540 comes to mind. One of the model comes with a decent 380Watt power supply but if that isn't enough. You can always find Fortron Source power supply at a decent price with plenty of wattage to throw around.
6. Power supply is the core of your system. In fact, all system should be built based on the power supply. You seemed to know that already. That is good. 18A on +12V should be minimum. The weight has to be quite a heft and efficiency is about 75% to start. 80%+ is better. For the Motherboard, you need a 24pin type main power supply connector. Make sure the case power supply has (for temporary use) and the future ones to have them as well. Also, get the ones with PCI-Express connector for future more powerful video cards installation. 450Watt should be minimum for single video card layout. 500-550Watt SLI certified should be minimum for dual video card layout. You might not need it now but as more funds become more available for you to burn and the SLI boards price became extremely affordable (they're about 100 bucks right now), you can readily transfer everything and not have to buy a new powersupply for it.

I hope that helps!

This is the best bunch of forum responses I've ever gotten, thank you all! I will consider all this once I've gotten some sleep and post here once I think I've made some progress. Thanks for all your feedback!

I have purchased the computer, considering heavily your suggestions along with some other considerations.

I decided to reuse an old ATX Case (Good, just beige and ugly and a little bent) with my old 350W Power supply (Reasonable quality). I've also dug out my old DVD-ROM and CD Burner, and for now I'm going to wait on purchasing a DVD-Burner.

So all that leaves me to get is: mobo, RAM, hard drive, and a processor. I am going with the ASRock/3200+ as suggested by mdd and vascular, Mushkin memory since I've had good experience with them before, and then a nice SATAII 250gb Hard-drive - Since storage is probably my biggest concern, and the price-per-gb is SO much better, especially considering the improved interface.

RAM: Mushkin ENHANCED MEMORY 1GB (2 x 512MB) 184-Pin DDR SDRAM DDR 400 (PC 3200) Unbuffered Dual Channel - OEM - $80
Mobo: ASRock 939Dual-SATA2 Socket 939 ULi M1695 ATX AMD Motherboard - Retail - $71
Hard Drive: Western Digital Caviar SE16 WD2500KS 250GB 7200 RPM SATA 3.0Gb/s Hard Drive - OEM - $110
Processor: AMD Athlon 64 3200+ Venice 1GHz FSB Socket 939 Processor - Retail - $160

After shopping around pricegrabber, I still went with newegg;
Total: $421 + $17 Shipping = $438

Though I can't go back now, I'm still interested in what you have to say about the build/what your first upgrade would be. abs0lut3, I almost approached your idea for the 6100/6150 onboard graphics, but I couldn't find any evidence it was nearly as fast as my 9700 Pro so I went with the dual board. Really good suggestion, though, I'll be reccomending that board to a friend soon for his computer.

Thank you all for your awesome suggestions, you rock!

Good to hear melek.

Absolute is right I messed up with the case but I did update it.
Why absolute recommend a 450watt power supply or even an sli power supply while also recommending an micro atx is beyond me. The only thing with power supply is getting a decent one. With your budget and wanting to use your video card you did good.
I also agree with absolute you can get hard drives cheaper and retail stores sometimes but ONLY AFTER mail in rebate.