The pc entering in pwoer saving mode and

If you getting this error then you won't be able to open computer in safe mood, Because this error message indicate that there is no proper bootable media selected or there is no OS in your Hard drive.
First thing you can do is go to BIOS and check what is your First boot device selected, if it is other then Hard drive then change it Hard drive and save setting and come out of it.
If there is any media, like Pen drive or any CD then remove it and start your computer.
If still you have same problem then I am afraid that your OS is Corrupted.

sounds like the hot key's have been pressed and it's in external mode. Press the FN +the F-key that looks like a monitor.

Hello, just start the computer an while starting (bios post) touch the del or esc or f2 or f4 just try one of theese when you can enter the bios menu then you go to start order and you choose first dvd/cd rom and second hdd0 always go to save it and exit, the computer wil restart then put in the cd/dvd rom drive the windows cd, restart the pc and when it says some thing like push enter to boot from cd/dvd rom then you push on enter and follow the instrucction till the end!
success!

You have to update the BIOS

http://h20000.www2.hp.com/bizsupport/TechSupport/SoftwareIndex.jsp?lang=en&cc=us&prodNameId=316715&prodSeriesId=316713&swLang=8&taskId=135&swEnvOID=181

Reboot, start tapping the F8 key when the boot screen first appears, then select safe mode. If you can start in safe mode, go to My Computer/r-click on the C: drive and select Properties from the menu, then select the tools tab, then click the check now button under Error-Checking. Provided you have been able to get that far, after you check for errors, then do a defrag of your hard drive while still in safe mode.

how did you know your CPU IS okay... DID YOU TRY TO PRESS YOUR KEYBOARD numlock or caps lock, IF YOUR COMPUTER IS ON BOOT PROCES?? IF NOT DISCONNECT YOUR vGA apadter from your cpu if your monitor didnt show any screen message then, you have a problem in your monitor

Try this first : Load the bios (F10 - vista or F1 - XP), Load setup defaults F5. then Save changes F10, and try restarting your pc.
Secondly, after restarting your pc, on the HP invent screen, keep tapping on F9 for the diagnostic test
If theres no any error message, press any other key ACCEPT for the 'R' key to restart or repeat the test.
Other sollution ----------------------
Try loading into safe mode F8, select on the safe mode and let the computer stays into safe mode for sometime.
If the pc doesnt restart, it means theres no any HW problem in ur pc. If it does the same, it means, you will need to check your Power supply, M/board with your tech

Try to enter in to BIOS by restearting the notebook (Pressing F2 function, if the notebook enters in to bios then no need to worry. after theat i suggest you to reinstall the notebook to original factory settings dy the recovery disks.

your known config is also probably not working .
try to format and re-install the boot partition.
this means your drive c: , leaving your data intact.

Try to change the RAS...