The MacBook replaces the iBook, with an Intel processor, magnetic Magsafe power connector, integrated iSight camera, and 13.3" widescreen display.

Your computer will not boot.

If your computer beeps three times, there is a RAM issue. Either you have insufficient RAM to boot, or the RAM you do have is faulty. First, access (Core Duo or Core 2 Duo) the RAM slots and ensure you have RAM installed. If you have two chips, first reseat them and try again. If that doesn’t work, try one chip at a time to see if one of the chips prevents the machine from booting. If none of these work, you may have a bad logic board.

If your DC-in board is bad, you will not be able to start your computer when it’s plugged into the wall. It may or may not run on the battery and the light on the power adapter will not light up at all (some power adapters do not have lights, so this may not apply to your computer). If this is the case, you must replace (Core Duo or Core 2 Duo) the DC-in board.

If your power adapter is bad, the computer will run off a battery, but it won’t charge. If your battery is too low, it will be difficult to diagnose a bad power adapter. The easiest way to test this is to borrow either a battery or power adapter to test in your machine. If you have the same problem with another power adapter, your problem is most likely the logic board. Compatible power adapters are IF113-046 and IF113-045.

If replacing the DC-in board and battery doesn’t fix your problem, then you need a replacement (Core Duo or Core 2 Duo) logic board. We carry logic boards for every MacBook model. There are some variations within specific processor speeds of MacBook logic boards. For example, the 1.83 GHz Core Duo logic board has 2 options: 3-wall or 4-wall heat sink connectors. The 2 GHz Core 2 Duo logic board has 2 options: Energy Star and non-Energy Star. Be sure to read the part description to ensure you are purchasing the correct logic board for your machine. Select your model for logic board options: Core Duo, Core 2 Duo (Late 2006), Core 2 Duo (Mid 2007), Santa Rosa, Penryn, or Early/Mid 2009.

As soon as you unplug the computer from a power source, it shuts off.

If your battery is dead, the computer will run fine off the power adapter, but will turn off when unplugged. A dead battery can manifest itself in many forms: It may not accept a charge (this particular symptom may also indicate a problem with the logic board), the computer may not recognize the battery, or the battery may be recognized as charged but fail to power your computer when the AC adapter is unplugged. We sell replacement batteries.

Even with a good battery, the fan speed must be high enough. The fan runs from 1200 to 7000 rpm at all times. If the fan speed is 0 or very low, the computer will not run when unplugged. Find a widget called iStat Pro from bjango to check the fan speed. This widget also reports battery health, cycles and charging status. I would love for it to just be the battery, but if you have this problem, even a new battery will not help. I tried cleaning mine and that did not work. Replacing it worked perfectly.

Try booting off an OS X DVD (or an OS X on a USB key). If that works, then it means the MacBook is working, but the hard disk is dead. Replace the hard disk and reinstall OS X on it.

The computer displays the flashing question mark when it can’t find a bootable operating system. This could be because your OS is corrupt, the computer doesn’t have enough RAM, or your hard drive is failing.

Try booting off an OS CD. Run Apple’s Disk Utility and try to repair the disk. You could also try Alsoft’s DiskWarrior. If this fails, reinstall your operating system. If you can, erase the hard drive prior to reinstalling the OS.

This is quite rare. If you have insufficient RAM for your computer to boot the operating system, you may get the flashing question mark. Installing more RAM (Core Duo or Core 2 Duo) or downgrading to an older operating system will fix this. You need 128 MB RAM to run OS X 10.0-10.4, and OS X 10.5 requires 512 MB RAM.

The hard drive may have been erased, corrupted, or damaged. If the hard drive has been erased, format it as HFS+ and reinstall your operating system back onto it. If it is corrupted or damaged, you need to replace (Core Duo or Core 2 Duo) it. Failing hard drives can display intermittent data corruption prior to failing completely. They often gradually get louder and start to click. If your hard drive is making abnormal clicking noises but still works, back up your data immediately and replace the hard drive. Any of our 9.5mm SATA hard drives will work in your computer.

The screen is very dark, but everything else seems to be running. If you get in close with a flashlight, you can usually see the image faintly.

If your backlight isn’t working, the inverter may be bad. Other parts that may be bad are the display or the logic board. If your backlight fails intermittently while moving the display, the problem is with the inverter cables. Otherwise it is impossible to test for damaged parts without replacing them one by one. If you are comfortable taking apart the display assembly, replace the display inverter first, then replace the LCD. If you are not comfortable with this, you can replace both parts at once by replacing (Core Duo or Core 2 Duo) the display assembly (Core Duo, Core 2 Duo, or Santa Rosa/Penryn). If this still doesn’t solve your problem, you need a new logic board.

The computer boots, but the trackpad and keyboard do not work, and USB devices (such as a mouse) do not work.

This is uncommon, but it does happen. The problem arises as a result of the design of the MacBook. The section of the board with the ports and the section near the fan slot are grounded via the metal shield on the lower case. Screws in these areas complete the ground circuit for the logic board. If a logic board is tested while not in the case with these screws installed, the result can be a short in the logic board. When this happens, the trackpad, keypad, and input devices do not work. The only solution is to replace (Core Duo or Core 2 Duo) the logic board.

Nothing above matches your problem, or you’ve tried a solution suggested above, but it didn’t help.

If you lose firewire, USB, audio or ethernet, the only thing to blame is the logic board. Because there are many components of the logic board, numerous possible symptoms indicate logic board failure. Any one of these components can fail and leave the others intact. If you lose the use of another component of your computer, such as the display, battery, or even power, and replacing the apparently non-working part didn’t fix the problem, it is possible that the logic board may need to be replaced (Core Duo or Core 2 Duo).