G5 PRAM reset and boot from CD or HD not working

Here's what I did, in order, and the results:

1) Booted up. Received login screen for Leopard, didn't know the password and wanted to reinstall OSX anyways to sell.

2) Booted to AHT CD that came with machine. AHT loaded successfully.

3) Decided to run AHT (Extended) to test before sold.

4) after 10:59, AHT froze during RAM test. Seemed like normal behavior.

5) 3 hours passed, suspected problem as AHT was still stuck at 10:59 RAM test. Fans Loud. Hard power off using front panel button.

6) had 3.5GB ram installed previously. Removed 2x25MB chips leaving 6x512MB chips installed,

7) booted to AHT CD. Ran Quick test. All passed.

8) attempted to boot to OSX tiger DVD in order to install fresh OSX. Chime but Would not boot.

9) attempted to boot to HD. Will not boot.

10) unplugged machine. Waited >2mins. Tried to boot again. No luck.

11) unplugged and pressed SMU reset button 3 times. Powered on. Chime still, but no boot.

12) pressed opt+PR. Didn't do anything except initial chime. Sometimes mouse LED goes out (plugged into keyboard)

13) pressed opt+OF. Open firmware loads.

14) typed "reset-nvram" ok. Typed "set-defaults" ok. Typed "reset-all" frozen.

15) hard restart. Tried numerous bookings. Would not boot original 10.3 install disk or 10.4 off-the-shelf disc or HD system drive. Will boot AHT disc.

16) will boot to source select when holding option but neither boot to HD or Boot to install disc works, even though source selection screen detects OSX on system drive and Install disc in CD drive.

17) ran AHT quick again. All pass.

Any ideas???