File server shopping list, advice?

I've decided to build this thing, partly for the experience (first ground up build) and partly for the $800 I'll save not buying it from Dell (although, they'll probably see me for the next one). This will be for a small business workgroup (<5 users). I want at least raid1. It won't do much except file serving unless I find something cool for it to do down the road .
I don't know about a power supply though. I was thinking >400W with sata connectors. I'm also not sure all this stuff will work when it get it together. Can you tell me if there are any incompatibilities here? Eventually, I'll probably add drives and whatnot, but not for a couple months.

ANTEC Performance Plus Metallic Gray SOHO File Server Case without Power Supply, N82E16811129124 $66.50

TYAN "Tomcat i7210 (S5112G2NR)" E7210 Chipset Server ATX Motherboard For Intel
SATA/RAID: 2x SATA with RAID 0,1,1+0, 4x SATA with RAID 0,1,10 by Sil3114
N82E16813151133 $231.00

Intel Pentium 4/ 2.26 GHz 533MHz FSB, 512K Cache – Retail Northwood Socket 478
N82E16819116141 $114.00

(2) Crucial 184 Pin 512MB ECC Registered DDR PC-2100 - OEM
Speed: DDR266(PC2100)
Type: 184 Pin DDR SDRAM
N82E16820145057 $130.00 ($260.00)

(2) Seagate 160GB Barracuda 7200.7 7200RPM SATA, Model ST3160023AS,
N82E16822148018 $106.00 ($212.00)

SONY 52X CD-ROM, Model CDU5212, OEM
N82E16827101126 $18.00

Microsoft Small Business Server 2003 Standard Edition $438.00

Subtotal » $1,339.50

Any reason you're getting a 533mhz fsb instead of the 800 that the board will support?
Double check that it supports registered ram. It said it did on newegg, but didn't mention it at another site, so you might want to verify it.
I don't see any other problems.

Hey, you're right on that, cheers! Tyan's site says it supports unbuffered ram. I was looking at the 533 only on price. I figure I'm only going to be using it for files and didn't need that much muscle. I just looked at newegg's ram, and they only have two 512 EEC unbuffered choices, and both are PC3200. Looks like I'll just get an 800fsb. The Kingston is 2.6V and the Crucial is 2.5V. What does that mean to me, anything? For a power supply I was just shopping by maximum power, I figure at least 450W should be plenty. One says something about an sata connector, I'm guessing that's something I'll need. Anything critical about power supplies I should know?