no starting tone just the apple then lightblue screen

Have you looked here?

Could be bad directory on disk try the /sbin/fsck -fy startup:

1. Start up in single-user mode by holding Command-S after restarting the computer. Note that single-user mode always uses the US English keyboard layout.

2. Type these commands, each on a single line followed by Return:

/sbin/mount -uw /

3. If the computer responds with "System Modified" type(run) /sbin/fsck -fy again until it stops modifying the system files. Then type

rm -rf /System/Library/SystemConfiguration/ApplicationEnhancer.bundle

reboot

4.If the issue persists, use option A or B from here.

Good Luck,

N.