Overheating

Frequent overheating will damage the motherboard! Here is an expanded article on heat and laptops.

Symptoms:

The laptop starts beeping, freezes, restarts by itself or shuts down after it has been on for some time, typically 10-15 minutes or more. If you start it again, it does the same thing after just a few minutes.

Troubleshooting:

Most laptops overheat because the fan intake is blocked either from placing the laptop on a soft surface or by dust. In either case you will need to let it cool down before turning it back on (may take up to 30 min). If you suspect that dust is blocking the fan/heatsink, get a compressed air can and try to clean it now (that will cool down the laptop too).

Sometimes overheating is caused by a fan malfunction. If the fan is completely stuck, the laptop will show an error message immediately after starting. However in rare cases the fan’s fins are just loose or broken and won’t move enough air to cool the laptop.

In either case you should try cleaning the fan(s) and heatsink(s) with compressed air. That is best done outside, as usually there is a surprising amount of dust accumulated in there. If the laptop continues to overheat, you will need to bring it to a repair shop.

Also if you have dropped the laptop, the screws holding the heatsink may have broken off. In this case the laptop will overheat in just a couple of minutes as the CPU has lost contact with the heatsink and is not cooled at all.

Motherboard

A motherboard failure on a laptop that is out of warranty would usually mean that… it’s time for a new laptop. The price of a new motherboard is usually higher than the current value of the laptop.

Symptoms:
Plug in the power adaptor and try to start the laptop.

Nothing happens.
The “ON” light comes on, the fan spins, but nothing on the screen (black) and you can’t hear the HD working after 10-15 sec.
The “ON” light comes on, the fan spins, but after a few seconds the light goes off.
After pressing the “ON” button the screen stays black and you can hear a quiet high-pitched sound coming from the laptop.
Troubleshooting:
Look for the “lid closed” switch and try pushing it a few times. It’s usually a small switch near the hinges that is pressed when the lid(the screen) is closed. Sometimes these switches get stuck in the “lid closed” position that results in black screen(no backlight) or non-starting laptop. Also some laptops have a magnetic switch (newer Dell’s and most Apple’s), that doesn’t get stuck.

Test the laptop with another power adaptor. Although not common, the adaptor can fail and not supply the needed voltage even if it has a green “power on” light that lights up when you plug it in. Even if you measure the output voltage and it’s OK, the adaptor may have failed and wouldn’t supply that voltage under load (typically 3.5A to 6A). You can use an universal adaptor or go to an independent repair shop and ask them to check it (some shops will try to charge you for “estimate” for doing just that, so ask in advance).

Reset the RAM. See the article on RAM failures for instructions.

Remove the hard drive and the CD/DVD if it’s easily removable.

Finally try to start the laptop again with only the power adaptor plugged in and with the RAM reset and all removable components and the battery out. If there’s still nothing on the screen, you will need to bring it to a repair shop.

USB Box

 USB Box

The best way to access your data when your laptop has a serious problem and wouldn’t start is to take the hard disk out and install it in an external USB box. These boxes are ridiculously cheap – starting at around $10-$15 and the whole transfer of the HD takes about 5 min. Then you will be able to access all of your files on another computer (even at an Internet cafe) and print whatever you need or copy the data to a CD.

This procedure is easily accomplished on most laptops, as the hard disk is usually held by 1-2 screws and is very easy to remove. However that will usually affect your warranty, so check the laptop’s documentation before starting.

However there are a few exceptions: on most Apple laptops and some light weight Sony and Toshiba models the hard disk is hard to remove as the laptop has to be disassembled completely to reach it. Removing the hard disk on these models would also invalidate the warranty.

Also some sub-laptops have a smaller hard disks, not the standard 2.5″ but 1.8″ HDs. Hitachi’s 1.8″ drives have the same pin configuration as the 2.5″, however Toshiba’s 1.8″ drives use their own special pin connectors (they are widely used in the hard disk based iPods). Finding an external USB enclosure for them is not that easy. It usually has to be preordered and would take a few days to arrive.

As an alternative to using USB enclosures, there are cable adaptors for standard 2.5″ HDs (including Hitachi’s 1.8″) and Toshiba 1.8″ HDs that would let you connect them to a standard IDE cable on a desktop PC.

* If you have password protected your laptop’s hard disk, transferring it to an external USB box won’t work. The only way to access it would be to connect it directly to another computer by using an IDE adaptor and then remove the password.

LCD Failures

Hardware failure – LCD, inverter, cable or backlight

Symptoms:

The laptop appears to start as usual but the screen is black, if you move it, it turns on and works properly. Failed cable.
The laptop appears to start as usual but the screen is very dark, although it changes colour a little and you can see a very feint image. Failed inverter or cable 90%/10%.
Immediately after starting the screen has dark pink/red tint and turns dark after a few seconds. Failed backlight.
The screen flickers a few times but then turns dark, if you move it or tap it lightly on the sides, it flickers again. Failed cable or LCD 50%/50%.
Screen is either black or white (no picture) and external monitor works. Failed cable or LCD 30%/70%.
There are stripes on the screen (either vertical or horizontal) that change when you move the screen or tap it lightly on the sides. Failed cable or LCD 10%/90%.
In all above cases, if you plug in an external monitor, everything shows fine on it (you have to plug it in before starting the laptop and may need to press the “Fn” key together with one of the “F1″ – “F10″ keys to make the laptop recognize the external monitor).

Troubleshooting:
If the screen is black, look for the “lid closed” switch and try pushing it a few times. It’s usually a small switch near the hinges that is pressed when the lid(the screen) is closed. Sometimes these switches get stuck in the “lid closed” position that results in black screen(no backlight) or non-starting laptop. Also some laptops have a magnetic switch (newer Dells, most Macs, etc.) that doesn’t get stuck.

The most common failures are (in this order): inverter, “lid closed” switch, cable, LCD, backlight.

RAM Failures

Bad RAM is somehow harder to diagnose as similar symptoms may be caused by software problems, other hardware problems or even motherboard failure. However if you experience any of these symptoms, you should check for bad RAM before attempting any other troubleshooting.

Symptoms:
Windows doesn’t start showing different error messages each time.
Windows crashes (blue screen) or freezes frequently.
Windows crashes as soon as you try to start a program.
Unexplained random crashes and freezes without error messages.
Troubleshooting:
Download Memtest86+ and burn it to a CD or make a floppy. For CD get the “Pre-Compiled Bootable ISO (.zip)” and for floppy (if you can start your laptop from a floppy drive) get the “Pre-Compiled package for Floppy (DOS – Win)”. If you are making a CD, you will have to “burn” the ISO image to the CD, not just copy it. There are numerous guides how to do that with different CD burning software (you cannot do it with the build-in Windows CD burning). In general you need to find where on the menus of your favourite CD burning program it says something like “Create CD from Image” or “Burn Image to Disk” or similar. Then select the .iso image file and burn it. If your laptop crashes a lot and you cannot make the Memtest CD or floppy, ask a friend or talk to your local repair shop and ask them to make one for you (it probably will be $5-$10).

Start the laptop from the CD/floppy and let Memtest86 run for a couple of hours. To start your laptop from the CD you may need to select a temporary boot device by pressing F12, F11 or F8 as soon as the logo appears on the screen (2-3 sec. after turning it on) or immediately after entering the BIOS/HD password if you have set one. If that doesn’t work, you will have to change the boot order in the BIOS. To do that try pressing F1, F2 or “Esc” (for Toshiba) to get to the BIOS settings and make the CD the first booting device.

If Memtest86 finds errors (there usually will be thousands of them) try removing one of the RAM chips (if your laptop has two of them) and run Memtest86 again.

Most laptops have two RAM slots that are easily accessible under a tab on the bottom. Others have just one slot there and the other is under the keyboard, on some there is RAM soldered on the motherboard (Toshiba), and a few laptops have just one RAM slot.

Removing laptop RAM: remove the screws, touch an exposed metal part of the laptop with both your hands (usually the VGA connector has two visible screws that you can touch to discharge any static electricity), then release both clips that hold the RAM and it will pop up. Hold the RAM on the sides (avoid touching the chips) and gently pull it out. To install, insert back the RAM and gently push it down until it locks in place.On some laptops the RAM is under the keyboard, or one chip is on the bottom of the laptop as described above, and another is under the keyboard. It is usually very easy to remove the keyboard on almost all laptops. Try to find the service manual for your model and find the description there. Alternatively, there are step-by-step picture guides on the Internet for most laptop models.

Memtest86 will run until you stop it by pressing “Esc” key. If your laptop freezes or restarts by itself while running the RAM test, it either is overheating or has another hardware problem.