How to open the evo 500 compact black box - Compaq EVO 500 DT/MT S478 P4 Motherboard (DSBB277498001MOTHERBOARD)

Hi maybi,

The evo's have two senarios that you may be facing.

First is Smark Cover locking. If you enable the Smart Cover Lock and cannot enter your password to disable the lock, you will need a Smart Cover FailSafe Key to open the computer cover.
You will need the key in any of the following circumstances:
Power outage
Startup failure
PC component (for example, processor or power supply) failure
Forgotten password,

If you don't have the Key, To obtain a FailSafe Key:
Contact an HP reseller or service provider.
Refer to the HP's Web site (www.HP.com) for ordering
information.
Call the appropriate number listed in the warranty.
To open the computer cover:
1. Turn off the computer and any external devices.
2. Disconnect the power cord from the power outlet, and disconnect
any external devices.
3. Using the Smart Cover FailSafe Key, remove the two
tamper-proof screws that secure the Smart Cover Lock to the
chassis.
4. Remove the Smart Cover Lock.
To reattach the Smart Cover Lock, secure the lock in place with the
tamper-proof screws


Or the non- Smart Cover Case:

1. åWARNING: Before removing the computer cover, ensure that the
computer is turned off and that the power cord is disconnected from the
electrical outlet.
2. Turn off the computer and any external devices.
3. Disconnect the power cord from the power outlet, and disconnect
any external devices.
4. Press in the button on each side of the front bezel to release the
quick release cover latches.
5. As you slide the computer cover forward, release the buttons and
allow them to return to the original position, then lift the cover up
and off the unit.
✎ To replace the cover, reverse this procedure.
Good Luck,

Mark