FC6 - X server can't start - embedded ATI Rage XL AGP - Dell PowerEdge 700

After converting from FC5 to FC6 (clean install, NOT an upgrade), I can
no longer get my X server to start.

Target System:
  - Machine: Dell PowerEdge 700
  - Integrated Video: ATI Rage XL AGP
 

Snippets from key files:
/etc/sysconfig/hwconf -- includes the following:
    class: VIDEO
    bus: PCI
    detached: 0
    desc: "ATI Technologies Inc Rage XL"
    video.xdriver: ati
    vendorId: 1002
    deviceId: 4752
    subVendorId: 1028
    subDeviceId: 0167
    pciType: 1
    pcidom:    0
    pcibus:  3
    pcidev:  e
    pcifn:

/etc/X11/xorg.conf - includes the following:
    Section "Device"
	    Identifier  "Videocard0"
	    Driver      "ati"
    EndSection

/var/log/Xorg.0.log -- end with:
    (II) Primary Device is: ISA
    (II) ATI:  Candidate "Device" section "Videocard0".
    (EE) No devices detected

Any advice about what to do next would be appreciated.
- Charlie Butterfield