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PRAM stores certain system and device settings in a location that Mac OS X can access quickly. Exactly which settings are stored in the computer’s PRAM varies depending on the type of computer as well as the types of devices and drives connected. To reset PRAM: 1. Shut down the computer. 2. Locate the following keys on keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in Step 4. Note: If the keyboard does not have an Option key, use the Alt key instead. 3. Press power button. 4. Immediately press and hold Command-Option-P-R keys. Important: You must press this key combination before the gray screen appears. 5. Hold down keys until the computer restarts, and you hear the startup chime a second time. 6. Release keys. if you still have problems call us +1-855-517-2433

LED #1 = Power available. If no LED is visible: • Verify AC source • Verify known-good AC cable is connected • Verify cable connection between AC inlet and power supply • Verify cable connection between power supply and logic board • Verify power supply LED #1 + LED #2 = Power available, and system is powered on. If second LED is not visible when power button is pressed: • Verify power button connection to logic board • Verify power button functionality • Verify cable connection between power supply and logic board • Verify power supply • Verify logic board LED #1 + LED #2 + LED #3 = Power available, system is powered on, and video card found . If third LED is not visible after power on: • Verify that MXM video card is seated properly • Verify logic board LED #1 + LED #2 + LED #3 + LED #4 = Power available, system is powered on, video card found, and internal LCD found. If fourth LED is not visible after power on: • Verify cable connections between LCD pane