Safe Boot , Serial ATAPI Initial device configuration did not complete successfully.2

Question

clean install OS Snow Leopard and up to 10.6.8.
I install Mavericks & restart computer,
it goes to white screen with Apple Logo and spinny thing at bottom, then after about 2 minutes the Apple Logo changes to a grey No Entry sign.
Now I use safe boot, the message is
" Serial ATAPI Initial device configuration did not complete successfully.(failedCommandInfo = 0x1)
Still waitting for root device"
I can use Snow Leopard DVD startup & chooen 10.6.8 (Macintosh HD) start Disk.
What happen to intall Mavericks of my case? Please HELP! THANKS!
Mac Pro, Mac OS X (10.6.8)                                        

Answer 1

If you want to preserve the data on the boot drive, and it's not already backed up, you must try to back up now, before you do anything else. It may or may not be possible. If you don't care about the data, you can skip this step.
There are several ways to back up a Mac that is not fully functional. You need an external hard drive to hold the backup data.
1. Boot from the Recovery partition or from a local Time Machine backup volume (option key at startup.) Launch Disk Utility and follow the instructions in this support article, under “Instructions for backing up to an external hard disk via Disk Utility.”
2. If you have access to a working Mac, and both it and the non-working Mac have FireWire or Thunderbolt ports, boot the non-working Mac in target disk mode. Use the working Mac to copy the data to another drive. This technique won't work with USB, Ethernet, Wi-Fi, or Bluetooth.
3. If the internal drive of the non-working Mac is user-replaceable, remove it and mount it in an external enclosure or drive dock. Use another Mac to copy the data.