New/Recycled Gaming PC - AMD ~$300

[Treebeard]

I would like to build a new PC for gaming, to replace my current 4-year old Dell (PIII800mhz based).

I have a very limited budjet, 200-300$, but also less parts to buy since I plan to recycle several expensive ones. I need help in determining which parts to buy to compliment the recycled ones, and how to assemble everything. I have some experience tampering with my PC, but never assembled one from parts.

In general - I plan to buy a new Case / PSU / Mobo / AMD Cpu and Memory
I do not plan to overclock anything.

These are the parts I plan to recycle:

HDD:
- 80gb Western Digital, 7200 (primary)
- 20gb WD 7200 (old one, need details on how to install both)
Video Card: Rosewill Radeon 9600XT, 128mb, 128bit, AGPx8
(its currently working as x4 on my old mobo, need it at x8...)

Sound Card: SB PCI
Pri Optical: CDx40?52? dont recall
LAN/Modem: Network Card + Surfboard
Monitor/Peripherals - covered.
OS: Win2KPro (personal purchase, probably can be reused)

PSU: I got a Rosewill 300W for $10 at newegg, didn't work with my PIII system, so its either dead or not-compatible - is it garbage or usable?
I realize it was probably a waste-buy, and don't mind paying extra for stability.
______________________________

Current plans for the new System, (?) means I'm looking for a reliable and value oriented component:

Case: CoolMaster Centurion 5, CAC-T05-WW, newegg - looks like a good option

PSU: (?) - not sure how powerful it needs to be, best reliability/price?

Mobo: (?) - these get really confusing, with costs ranging from $40 to $100+, what should I look for?

CPU: AMD Athlon (?) - XP? Sempron s754 (gimped 64)? I read up on this but am still confused which AMD is the most cost-effective for my needs. I probably won't need 64-bit capabilities. This Sempron64 looks interesting, $64 newegg

RAM: 516 of something (?)

Video Card: 9600XT AGPx8, see above

HDD: 80 + 20, I want to use both of mine
Pri Optical: Keep my current CD for this upgrade, add or replace with something better later.

The cornerstone of the system is probably the Video card - I want to buy components that will compliment it in effectiveness, because it won't be replaced soon.
I would prefer to purchase everything from one supplier, like newegg.com.

Any help and advise is highly appreciated. Thank you!

[jayb1234]

You are also going to need to get a new copy of windows. You can't reuse the Dell one on a new build.

Sparkle power has some ATX power supplies that might fit your budget.

One of these motherboards would be ok.

[spartan015]

no it said that its personal version so i think its fine, id recommend 1gb of ram rather then 512, around 80 dollars usually...

[Treebeard]

Coolmaster Case... same as above and:
ASUS K8N-E Socket 754 NVIDIA nForce3 250Gb ATX AMD Motherboard - Retail
AMD Sempron 64 2600+ Palermo 800MHz FSB 128KB L2 Cache Socket 754 Processor - Retail
CORSAIR ValueSelect 512MB 184-Pin DDR SDRAM Unbuffered DDR 400 (PC 3200) System Memory - Retail - its $40
COOLER MASTER eXtreme Power RS-430-PMSR/P ATX12V Max: 400W, Peak: 430W - Retail
I was looking at Sparkle, and they seem to be slightly higher priced. Is there a difference in reliability?

Pardon the slight confusion with the OS, my PC came with WinME, and after a year of horror and instability, I bought Win2KPro. Edited that in after Jayb posted.

I really don't mind the 516mb, since most games I play aren't that high-end, and its sufficient for my cad/graphics work. When I find the extra $40 or $70, I'll just add another stick. Its possible to add 1gb and get 1.5gb combined, if the mobo supports 2 DDR400 sticks right?

Right now my total is ~$260, so with shipping I should still be within my maximum budget.
I just hope I'm not missing anything. o_0

[jayb1234]

The 2kpro will be ok to reuse.

Sparkle and coolermaster PSUs are pretty similiar in quality. Either should be fine.

Here is the link for the Motherboard manual, It has a list of tested RAM for the board, which has 3 RAM slots.

Also if you can afford it, bump that processor up to a little better one with a bigger cache.

[Treebeard]

A review of that Sempron line suggests you're right - the 2800 one has a bigger cache and still in the same price range.

Spartan seem to be right about the RAM, that manual lists that you can't fit two dual sided sticks at DDR400 (if I read that table correctly, only DS + SS combinations are allowed at that rate) so I'll consider getting the 1gb stick now.