Thanks everyone, MikeC and doing some further reading has helped me get a better idea of how much power is required. I will be patient and wait for my new psu. I still have components to get. I need to choose a case also.
It appears that the A64 will draw just about 8-11A and my current psu is to close to be comfortable. Besides, I will use it in the computer I build from leftovers.
I am looking at the dual rail Enermax 325 and the 300W Super Tornado for psu.
My silent PC has been a long time in coming.
AMD Sempron 3100 (Don't laugh, see below)
1GB Crucial 2 x 512MB sticks
20GB Maxtor or it will go in another machine with the old MB and Duron
Maybe a DVD burner.
I ordered a Sempron 3100 to see what it can do. I've had good luck with my Duron 850, which has held its own for a long time in everything I do except 3D games (my old Radeon 7000 based video does fine with most) and video encoding. I do get encode times relatively the same as the Mac our compressionist uses, so I am not expecting much of an improvement. I'm hoping that it might use a little less power than the A64. And there's not much 64 bit software out there yet.
I may get a Zalman AlCu or HT-101 for HSF. The CPU is OEM.
I'm getting a board that can take one of the regular A64 so if I want to replace it as prices come down, I can. I sorta want to try the Semperon because the low end A64 is now about what I paid for a K6200 some years ago.
The board is an ASUS K8N. I didn't want the extra garbage on the deluxe board. I have a nice Adaptec firewire card and will continue using it, so I don't need onboard firewire. And gigabit LAN is useless, since I don't have any other PC's with that. I am not that interested in the third-party SATA controller and will use the one on board. I don't need onboard sound (although it has it) and don't want onboard video.
I have a 9600XT. The 9600XT is the most powerful graphics card that is still passively cooled. INCORRECT the 9600XT has a small fan mounted to a heatsink. It is not passive. But it's okay with me because I can't hear it over the case fans and I am not accepting any less than this level of performance.
I still love the minimalist design of my Inwin A500 case although it is beige and poorly designed for good airflow. So it is hard to decide on a case. I'm torn between trading a bit of quiet for a bit of style. I end up suffering from the Sonata/BQE syndrome as they are the same price at my local store.
This is a very new board. People don't know about it yet, they mix it up with MSI's. I apparently am one of the first in line to buy the Semperon 3100 because a lot of people don't know it is a A64 based chip. LOL I am on the bleeding edge of the trailing edge with this stuff. All this was pretty cheap, so I'm not worried about replacing it.
There are a lot of urban legends out there about the Sempron 3100. People don't realize it is a socket 754 CPU and that it is based on the A64. It has all the architectural features but without a 64 bit instruction set. It has Cool 'n Quiet. At least this is what I have read.
EDIT: I must have Semper Fidelis on the brain, Sempron, Sempron.