RAID improves availability, but is not an alternative to a real backup via CD-RW or tapes. RAID does not protect your work from fires or viruses, and an ATA RAID 1 solution has almost the same availability as a single SCSI disk (SCSI disks don’t fail anywhere near as often) and far less performance.
The problem with AMD isn’t the processor, it’s the platform. While an AMD 760MP solution is obviously attractive, it doesn’t support PSE or PAE, PCI-X and will end up costing about the same as a similar performing uniprocessor Pentium or Celeron platform.
The first link I’m listing is to a Gigabyte board based on the Serverworks GC-SL chipset taking DDR SDRAM, about $300. Next, add a single 512 MB DDR SDRAM DIMM for about $100 (you need Registered ECC); Crucial and Kingston are good choices here with their lifetime warranties. Next up comes the CPU, and here I recomend a retail box Celeron and use the standard HSF for about $100, and get a decent chasis and PS for about $100 for a total of $600. Next comes the storage, and I figure you can get a CD-ROM or DVD-ROM and floppy disk for around $50, tops. With a running total of $650, you can then add in a Seagate Cheetah 10K.6 drive at 36 GB for around $175 (see link 3), bringing the runnint total to $825. From here, you have an entire system, ready to go with only one crucial component missing: backup.
For about $200 you can pick up a 20 GB Taravan ATAPI drive and for another $100 a fireproof safe for an enterprise-type backup solution, or you could go with a less expensive external hard drive, but this is of course more prone to failure and virui. In between is the CD-RW. Basically, it’s a pain to backup onto CD-RW with all of the disc swapping, but it would do the job, being less sensetive to virui and failure than an external hard drive, but nowhere near as safe as a tape drive.
Link 1: http://www.knowledgemicro.com/detail.php?p=MB-8EGXR&c=pw
Link 2: http://shop.certance.com/product.asp?sku=1948949
Link 3: http://www.newegg.com/app/viewproduct.asp?description=22-111-124&refer=pricewatch