Picked me up one of these.  Looks sexy.  Hopefully the card will work well.

HostRAID™ Serial ATA II controller supporting RAID 0, 1, & 10 for data protection and increased performance
4 Serial ATA 3Gb/s ports, PCI-X 133 MHz, low-profile form factor with Native Command Queuing, RAID 0, 1, and 10 for desktops, workstations and entry-level servers

Intel IA-32, AMD32, EM64T or AMD64 type servers
PCI 2.2 compliant systems
PCI-X 64-bit/66-133MHz
PCI 64-bit/66MHz
Support for both 3.3 and 5 volt PCI signaling

Details: http://www.adaptec.com/worldwide/product/proddetail.html?sess=no&language=English+US&prodkey=AAR-1420SA&cat=%2fTechnology%2fRAID+Controllers%2fSerial+ATA+II+RAID

Drivers: http://www.adaptec.com/worldwide/support/drivers_by_product.jsp?sess=no&language=English+US&prodkey=AAR-1420SA&cat=%2fProduct%2fAAR-1420SA

Update - card works beautifully.  My drives are happily migrated over, and everything is well.  Remember - Adaptec, and 3Ware.  Keep Promise away from your computers - and everything will be well, and stay that way.  Don't every use a Promise card.  Period.