I did end up building the new computer I said was thinking about making (See "Yummy Greek Food & Computers" from March 5). It is definitely one kick-butt system. I don't have all the pictures ready to post yet, but here are the guts of the system, for those techies who are interested.
Here is the motherboard, relatively bare, with just the new CPU -- an Intel Core2 Quad processor, 2.83 GHz, 12 MB of cache (the Q9550 processor). In this photo, the processor is mounted and bracketed into the system board. The system board is a Gigabyte GA-EP45-UD3P.
To assure that the CPU would not overheat, and in the name of making the system as quiet as possible, I used a Noctua NH-U9B CPU cooler. The thing is huge. However, in my tests, the CPU doesn't get warm at all. I have not yet figured out how to read the CPU temperature under Linux (I'm sure it won't be too hard once I find out) so I don't have any specific numbers to back-up this comment. You can also see the 4GB of memory (2 x 2GB) made by G.SKILL. This is DDR2 1066 (PC2 8500) memory and cost $53 bucks at Newegg for the set (not too bad).
Here we can again see the sheer massiveness of the CPU cooler. Also apparent are the many ports available on the motherboard. Particularly useful are the dual Ethernet ports. This allows me to connect one to the cable modem (so the system can act as a firewall for the rest of my network) and the other can connect to downstream devices on the rest of my network. These days, I have several IP telephones, the access point, and what will ultimately a single "guest PC" system. Occasionally I will connect a very old PC to the network that has my old chip programmer board.
Finally, we have the system board inside the case. The case is an Antec P182 - which has a reputation for being designed for silence. There were two issues I had with the case: First was my own fault, and it's that I found the case was much larger than I expected. Sure, the specifications were right there online, but when I saw 20"x20", I didn't exactly visualize the size of the case. It can hold a total of 6 hard disks (I have 1). Second issue is that the three fans inside the case are a bit on the noisy side, for an otherwise very quiet case. The fan on the top is particularly obnoxious and so I disabled it. It turns out that with the fan in the rear of the case, it pulls enough air through the system to keep it cool. If I start to see a problem, I'll probably look for quieter fans.
The video card is the ASUS EN9500GT TOP/DI/512M. It's a basic video card with good performance and a quiet cooling system (again, concentrating on quiet). It is based on the NVIDIA GeForce 9500 GT graphics processor, runs at 700 MHz, uses GDDR3 memory on-board, and has 32 stream processors. While not the ultimate gaming card for sure, I see no reason why this card won't drive a HDTV at 1920x1080 for basic X windows, older FPS games (like Quake 3 Arena), or viewing video without any real problem.
Not seen in the photos is the Corsair CMPSU-650TX 650W power supply. This has ample connections for everything that I have in this system and more. I decided to save some money by not getting cables that will remove from the unit if not being used. This may have been a minor error on my part because finding a place for the extra cables - even in a large case like the P182 - can be a little on the tough side. Actually, routing cables in general was difficult because I wanted to keep them neat, but from/to routing of the cables didn't always allow that.
The two things I took from the old computers - the Western Digital 640 GB "green" hard disk and the Pioneer DVR-110D DVD+-/RW drive - worked fine with everything else.
The following may help people who plan to install Linux with this Gigabyte motherboard:
Disk: Set the BIOS to AHCI, and use the Linux AHCI SATA module (ahci and sd_mod) for the SATA drive access. AHCI will allow greater flexibility and it's what newer systems are using. Don't confuse the AHCI disk management with the USB AHCI HCD. They are not the same. The SATA disk drives will appear as SCSI drives (/dev/sd*)
Ethernet: Use the Realtek 8169 driver (r8169) which also supports the Realtek 8111C, which is what's on the motherboard. I had trouble with the old r8169 module on the Gentoo live CD. I was only able to get the second Ethernet port to work reliably, and both were showing loads of dropped packets (even on the first non-functioning port that had no cable attached). As soon as I installed the 2.6.27 kernel, everything worked fine.
Parallel ATA devices (DVD drive, in my case): This is a JMicron chipset, so use the pata_jmicron driver in conjuncation with sr_mod (and will appear as /dev/sr*)
Audio: The Audio chipset is Intel's HD Audio chipset, and so this is the driver that needs to be available. On the kernel I'm using, it's the snd_hda_intel driver. The CODEC seems to be the Realtek ALC889A. I have not tried the SP/DIF port yet (or the audio through the HDMI cable on the video card). I hope to try that soon.
Firewire (1394A): I have not tried to use this. I don't have any Firewire devices (yet?)
Serial/Parallel ports: Yeah, there's one of each, but a header for using them isn't included. I have only found one place that sells this part, and it seemed a bit pricey. They do post the pin-out online and I believe it's standard enough where you could probably use a hunk of ribbon cable, a DIL IDC, and a DB25/9 IDC, and you'll have what you need. I decided to power the X10 controller with a PL2303-based USB-to-Serial adapter, and that works great (it appears as /dev/ttyUSB0).
In general, the GA-EP45-UD3P is a pretty Linux-friendly motherboard. Except for the Ethernet driver issues, I had no trouble getting this board to work. It works reliably, as well. No crashes.
For those interested -- the video card also seems to work OK with Linux. You can use the stock "nv" Xorg driver without acceleration. To get accelerated video, use the Linux driver from the NVIDIA web site. I will feel more confident about this once I have connected the computer to my HDTV through the HDMI port.
I am still in the process of trying everything out, and getting more familiar with the capabilities of the hardware. In a later posting, I'll summarize what I've found out. What I can say is that Firefox compiled so fast that I wasn't sure that it completed successfully. I also installed the CPU regulator drivers, and the unit takes about 75 watts when idle. So it is definitely much less power-hungry than running multiple smaller systems.
All in all, I think it was money well-spent. If nothing else, I helped give the economy a boost!!