System board also know as motherboard
A system board also known as motherboard or mainboard is the main circtuit board in any laptop. Unlike desktop PC system boards, laptop system boards come in thousands of different shapes and sizes. Laptop motherboards are model-specific. In other words, you cannot remove motherboard from a Toshiba laptop and stick it into a Dell laptop. All parts inside a laptop are connected to the system board, either directly via a connector mounted on the system board or through a cable.
In a typical laptop the following ports and components are permanently attached to the system board and cannot be easily removed and replaced without soldering:
1. Hard drive (HDD) connector.
2. CD/DVD drive connector.
3. Memory (RAM) slots.
4. Battery connector.
5. Keyboard connector.
6. Audio (headphone and microphone) jacks.
7. Volume control wheel.
8. USB ports.
9. Eithernet (RJ45 aka network) port.
10. IEEE 1394 (Fire Wire) ports.
11. Video chip and some other components and ports.
System board, processor (CPU) and LCD screen are the most expensive parts in any laptop. In some cases, when one of these three parts fails, it’s cheaper to buy a brand new laptop than replace the failed part. But each case is different so do your research.
The system board is mounted inside the laptop base assembly. In order to remove or replace the motherboard, you’ll have to disassemble the whole laptop.
SYSTEM BOARD FAILURE SYMPTOMS.
When a system board fails, you may experience the following most common problems with your laptop. 1. The laptop is completely dead. There are no LED light activity when you press on the power button or plug in a known good AC power adapter. 2. The laptop starts but the video output on the LCD screen or external monitor is garbled. Most likely this is related to the VGA chip failure. 3. The laptop turns on without video on the screen and the power LED starts flashing. 4. The laptop works fine with AC power adapter but will not charge a known good battery. If that’s the case, most likely there is something wrong with the battery charging circuit or DC power jack.
Laptop parts | Repair Man | 
December 26, 2008 3:45 pm
299 Responses to “System board also know as motherboard”
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Pages: « 12 11 [10] 9 8 7 6 5 4 3 2 … 1 » Show All
January 21st, 2011 at 3:43 pm
I have a Toshiba A75 and the battery charges when the laptop is off but when I turn it on and plug in a AC adapter it does not charge the battery.. Does that have to do anything with the motherboard.. someone told me that it did and to replace the battery and mainboard? is that right..
January 18th, 2011 at 4:00 am
i have the same problem, my laptop is also a thoshiba a300, it is a problem with the motherboard power unit.
January 13th, 2011 at 1:49 pm
Donald,
Could be memory failure.
1. Try reseating both modules. Maybe one of them not making good connection with the motherboard.
2. Try removing memory modules one by one. Test laptop with each module separately. One of the modules could be bad.
January 12th, 2011 at 4:14 am
Hi,
I have a compaq presario cq60. The power light comes on, the fan turn on and I am able to access the cd tray but nothing else seems to work. I have switched it on using battery power, ac power and in all cases it just turns on but no light no sound just the fan light.
What could be the problem?
January 4th, 2011 at 10:05 am
Jad,
Sounds like motherboard failure to me. Apparently the battery charging circuit failed.
If you take it to a repair center, most likely they will quote the motherboard replacement.
January 4th, 2011 at 9:51 am
Hi, I really need some help. I want to whats wrong before taking my hp pavllion dv600 to service centre. Problem is that the charger doesn’t charge the battery at all. Charger is fine with other laptops. I also charged battery through some other laptop and after that it works fine when plugged into my laptop until it finally dies. Laptop works absolutely fine till the battery has the juice. All the leds glow on pressing the power button. Even the around the charging port. So what could be wrong? Please reply
January 4th, 2011 at 3:03 am
did you know about Acer Aspire 4520 Touchpad Cable, mine is broken
December 24th, 2010 at 9:05 am
My DV-2000 Hp laptop screen flickers. When I hold or tilt it, it shows but as soon as I leave it, it freezes. It keeps getting worse.
Later, the speakers also stopped working, except when I use an external speaker.
I desire to fix it myself but don’t know how to start. Can anyone help?
December 21st, 2010 at 10:34 pm
buy another laptop
December 12th, 2010 at 5:57 pm
hi I have a problem with my cpu,,i mean my system board,,when i plug in the cord or switch on the avr its autmatically will on without switching on the power on in my computer,,,am mr. repairman,,what could be the possible problem with my s.u???…i check it all,,,i remove all parts like memory,videocard,the switch of the system..all parts i remove it instead the power supply…i chage allready jumper..the power supply is good
December 11th, 2010 at 1:34 am
Hi…..I have a problem with a Medion MD 96500 (MIM 2040)…when you switch on the screen lights up for a second and then goes dark…..there are images on the screen but not bright…..classic
inverter fault I thought….but I have changed the inverter 3 times with no effect…..I have checked that it is not the screen because I tried a back light from a broken screen and this does the same thing….Flashes once and off….so it looks like a power fault feeding the inverter…..but without a circuit diagram I am stumped………any ideas please
Regards Brian
December 7th, 2010 at 3:39 pm
Jayesh,
Test the AC adapter, maybe it’s not working properly. I would definitely test laptop with another known good adapter.
If the laptop still restarts with a new adapter, it must be some kind of motherboard failure.
December 7th, 2010 at 2:21 pm
Vincent,
Most likely you damaged the motherboard.
It’s necessary to disassemble the laptop and take closer look at the damage.
In most cases liquid spills not worth repair.
December 7th, 2010 at 9:13 am
jared,
Most likely this is motherboard related problem. CPU failures are not very common.
I believe the laptop would stay on all the time even with failed CPU.
December 3rd, 2010 at 6:19 pm
Hi! i noticed the laptop and motherboard your using for your example is a Toshiba a305 model… the same model im having problem’s with. When i press Power button, LED’s light up, fan kicks on, tries to access the cd rom, but turns off after about 3 seconds. The screen never turns on. it continues to turn itself on and off repeatedly unless unplugged. Ive tried new memory, tested hard drive, reapplied new thermal grease to all heatsinks, checked all cables were connected, etc. I shorted the CMOS battery on purpous to reset bios. I have a processor on the way that i purchased on ebay. Think i waisted my money? are these laptop’s known for bad motherboards? i couldnt find much info on the internet. Ive left everything unplugged except the power, and processor and fan and so ive narrowed it to motherboard or processor. Any ideas?
November 28th, 2010 at 12:30 am
Vincent,
Most likely the motherboard damaged.
It’s necessary to disassemble the laptop completely and take a closer look inside.
Turn it off and remove the battery. Do not use the laptop until diagnostics done.
November 28th, 2010 at 12:24 am
Hi, I accidentally poured a drink into my laptop coursing it to go off. Now it will not start or even acknowledge the ac power adopter. In short it’s dead, what do I do please?
November 26th, 2010 at 9:58 pm
Hi, I had a problem with my laptop. One day, when I turned it on, a few minutes later, it restarted by itself. So, I did some tests, I used it using a power adapter with no battery, and it restarted. I used it with battery and power adapater, still it restarts but when I used it with battery only, then I continued using it until the last drop of my battery. So, anyone can attest to me, if whats going on with my laptop? My laptop is Toshiba Satellite A300. Does anyone has the same problem with me and what did you do to resolve such problem?
Plz Reply
November 15th, 2010 at 8:32 pm
Could be memory failure. If you have two memory modules installed, try removing them one by one. Test the laptop with only one module installed. Try either memory module in either slot.
November 12th, 2010 at 2:00 pm
hii i have acer extensa 5630 with a problem power button
i plug ac adapter lid light on but wen press the button noting haven
are there any solution
October 27th, 2010 at 6:15 pm
Hi, I got a 3 years old Toshiba Laptop A200 and when i start my laptop the power is on but the LED of display and the LED of HD does not on( or no light at all LCD) even the fan start but after 10 seconds it turns off! I have to start several times to get it on. Then If i manage to go into window, The LCD screen will automatic off and won’t turn on after few times of screen saver or the function of automatic turn off LCD screen in window. It may happen once after few hours of usage. The CPU fan will turn on and off during the window operation. May i ask which parts need to be replace? Is it over heat or motherboard or vga failure Thanks.
October 23rd, 2010 at 8:09 pm
Hi, I had a problem with my laptop. One day, when I turned it on, a few minutes later, it restarted by itself. So, I did some tests, I used it using a power adapter with no battery, and it restarted. I used it with battery and power adapater, still it restarts but when I used it with battery only, then I continued using it until the last drop of my battery. So, anyone can attest to me, if whats going on with my laptop? My laptop is Toshiba Satellite A300. Does anyone has the same problem with me and what did you do to resolve such problem?
October 19th, 2010 at 3:02 pm
HI everyone
i have an HP Compaq Presario CQ60-111EM. Bought it from Ebay it worked fine few day before it stopped working . I search for a while and i found this awesome forum to with very good and reliable tips for laptop repairs. So lets discuss about my problem.
when i plug the charger in to laptop, power light and wirless button light turn on itself without pressing the power button and fans keep spinning until i plug the charger out, when i try same thing second time only power light comes on and fan does not spin at all, same thing happens again and again randomly, display does not come at all only black screen. charging light also comes on and dvd drive also work i guess becoze it comes out when i press the eject button, i can hear somthing spinning i think it is either hard drive or dvd drive. i took it apart , tried all basics things like reseat ram even tried different ram, tried different processor etc but nothing worked. i got nothing to test but going to buy multimeter to test it, but dont know what shud i test as i am not good to repair the motherboard but willing to learn infact keen to learn.
Does anyone know what cud be wrong with it, plz help me in this regard.
does anyone know anytype of source of learning motherboard repairs like weblink or books etc or anone briefly describle abt it.
thanks
October 14th, 2010 at 11:50 am
Hi,
After plugging in a wet power adapter (I know: stupid), the power light indicates that it works but the screen stays black and no fan starts. The adapter still works fine on other similar computers. The power light comes on also when the battery is in the laptop. Any idea if a short circuit or whatever could have fried the mainboard? Its a Toshiba Tecra M2.
October 14th, 2010 at 7:20 am
Yup i have tried that Mr. Repair man! but still doesn’t work!
and also i have tried removing HD too and the battery still the same thing happen nothing happen!Please help