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QUANTA Motherboard Identification Number

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What is QUANTA?

Quanta is considered to be one of the top OEM laptops manufacturers. Their OEM laptop motherboard is used by bigs laptop companies in the market like Dell, HP, Lenovo, etc. So we are going to see the QUANTA motherboard identification number in this article.

How to identify the QUANTA motherboard identification number?

The QUANTA OEM laptop motherboard part number starts from DA or DAO. Their part number consists of DA or DAO sandwiched by 3 to 4 letters with ‘MB’ letters. The Quanta motherboard P/N model CH3 is shown in the below image.

Quanta motherboard P/N model CH3
Quanta motherboard P/N model CH3

 

 

 

 

 

 

 

 

In the schematic diagram of this laptop model motherboard, you can easily find “PROJECT CH3” at the bottom right corner of the schematic pdf.

Quanta motherboard schematics label Quanta CH3
Quanta motherboard schematics label Quanta CH3

 

 

 

 

 

 

There are other board manufacturers are also there like :

  1. Compal 
  2. Quanta
  3. Wistron
  4. Inventec
  5. Pegatron
  6. MITAC
  7. CLEVO
  8. FIC
  9. MSI
  10. ECS
  11. Flextronics
  12. Foxconn
  13. Topstar

You can also have a look at our article for what kind of checking is used for laptop chip level repairing.

 

 

 

For more information on How to find a laptop motherboard part number, we have already mentioned.

 

You can also check our other laptop preparing help guides.

 

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How To Find a Laptop Motherboard Part Number

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How to find laptop motherboard number

How to find a laptop motherboard part number is one of the questions asked by newcomers in the laptop repairing field. All branded laptop motherboards like Acer, Dell, Lenovo and etc.

They do not manufacture their own motherboards. They used a third-party company to design a laptop motherboard to build their own laptop.

The entire third-party laptop motherboard manufacturer called it an OEM company/manufacturer. You may think, What is the difference between OEM (Original Equipment Manufacturer) and ODM (Original Design Manufacturer company.

Difference Between OEM and ODM

The OEM design company does the manufacturing of a product. But it does not include product design and research.

The ODM company does all of these. They put their own brand name and model into this laptop as their brand new model of laptop.

Let’s consider one example for finding a laptop motherboard number for ECS G550

We can consider one example of a product manufactured by ECS G550. It used different brands and models of laptop computer machines like TCL 610, ChangCheng E2000, FangZheng T5800D and etc.

We can confidently say they most of the current laptop companies are using OEM and ODM to build their laptops. All of those OEM and ODM companies are from Taiwan and their production base is in China.

There are popular companies in the market that are OEM and ODM based are:

  1. Compal 
  2. Quanta
  3. Wistron
  4. Inventec
  5. Pegatron

These OEM companies have taken a huge market percentage for the production of laptop motherboards in the market.

The second line of laptop mother manufacturers in markets are :

  1. MITAC
  2. CLEVO
  3. FIC
  4. MSI
  5. ECS
  6. Flexctronics
  7. Foxconn
  8. Topstar

In chip-level laptop repair, we can see different brands and models of laptops sent by customers for repair. After doing dismantling laptops we can find that they use the same motherboards.

So can found that their motherboard circuit, timing sequence, and repairing steps are the same. It is needed to know by us as laptop repairmen, how to identify the laptop motherboard’s part number and what si their OEM manufacturer company is. Best of luck to you!

 

 

 

 

You can also check our other laptop preparing help guides.

 

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Be a Laptop Desktop motherboard repair Technician

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Every laptop chip-level repair person is a newcomer at the start as he doesn’t know how to start and where to start. So we are here to remove the confusion from you. We will discuss the solution to problems in this laptop motherboard repair guide.

There are many technicians out there who will give biased opinions about how to do things. But we are here to give an honest opinion which is called laptop chip level repair. We have divided it into 4 parts so you can have better knowledge. So let get dive deep into it.

The basic electronic preparing knowledge you must know for laptop chip level repair:

1. The Analog and digital circuits.

2. What are The opened and closed circuits in laptop chip level repairing.

3. For doing chip-level laptop repair you must know what is “Signal” and “Timing Sequence”. Let’s learn them one by one :

1) Signal:

When the motherboard is in working it will send and receive different types of data and signals for the proper working of it. For laptops to work properly signal plays a very important role.

2) Timing Sequence

As the name suggests, the meaning of timing sequence is the meaning of two words “timing” and sequence. When AC current is provided to the laptop motherboard press down the power button until its starts and opens up successfully.

At the same time what will be happened is the circuit will send and receive signals in between their correct timings and sequences. It is required to be done to make the user unable to ready to use by the user, for this motherboard must be turned on successfully.

The timing sequence is important and must be get followed by the motherboard to start running. If one of the steps got missed or the timing is not correct then it will cause the laptop motherboard to not be on.

The market has most top brands, but most of them are using Intel or AMD chipsets. There the same chipset is using the same timing to start and run to power on the laptop. When we are able to handle these two chipsets which are Intel and AMD we can handle and repair any laptop easily.

Know how to test electronic components

A laptop chip level repair technician must know what type of components it is used in a laptop motherboard. He must also know how to test the component with proper tools and equipment.

Know the structure of the laptop for laptop chip level repair

You must need to know the struct of the laptop before repairing it. For example, you must know how to dismantle the laptop and the correct maintenance steps for it. Also, you must know the basic elements used in laptop manufacture for motherboards.

Laptops have other names also such as Portable, Notebook Computer, Laptop, NB, etc. Even in the current market laptop repair business is still maintained.  But compared to the laptop repair market desktop repair got a huge drop for repairing. We will see this in our chip-level repair guide for laptops.

The Level of Laptop Computer Maintainance / Repair :

1. Application-level laptop maintenance :

This level of laptop repair mostly consists of work in software and system os installation. For example :

1) Installing the operating system.

2) Installing sound card, Bluetooth, network card, graphic card, and hardware drivers.

3) Upgrading BIOS.

and etc.

2. Board level laptop maintenance :

This type of repair consists of working more on a swap-type board. For example, consider the following examples.

1) Replace CPU processor including the things like CPU heat sink and fan.

2) Replacing the existing hard disk or installing a new hard disk.

3) Replace the battery or install a new battery.

4) Do degradation or replace the existing RAM.

5) Replace a faulty keyboard or install a new keyboard in case want a new keyboard by choice( in rare cases).

6) Replace a broken screen or case of a screen that has lost its touch sensitivity if the screen is a touch screen.

7) Repacing wifi card if we want another card by any chance or already damaged / not working card.

8) And etc.

For performing this level of laptop repair the repairman should have a basic level of knowledge in electronics and types of laptop chip level testing methods. For example, he should know how to measure the multimeter to test the ohm values and voltages.

3. Component level laptop maintenance :

For performing this level of laptop repair the repairman should have knowledge about how to use a multimeter, Oscilloscope, DC Regulated Power Supply, Soldering Workstation, BGA Machine and etc. In this case, the repairman can replace the component over the laptop motherboard to solve the problem. The example of those replaceable components are :

1) Resistor, Capacitor, Transistor/MOSFET

2) Inductors / Coils

3) IC Chips

4) South Bridge and North Bridge

5) Discrete Graphic BGA Chip and etc.

4) Signal level laptop mainboard repair :

This is also called laptop chip level repair. You must know how to do measurement and analysis of signals within the laptop.

You can also look for: Difference Between Intel Core i3 i5 and i7 Processors

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Laptop Battery Charging Section Repair

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What is laptop battery charging section repair issues

In laptop chip level repair there is the main problem that comes in preparing is the laptop battery charging repair-related issues. It is one of the most reported issues by customers and enthusiasts.

The reasons can be anything but the main cause is that the laptop adapter is not able to provide 19v current to your laptop. More issues can be there like like motherboard issues. We will cover them separately in another blog.

 

How laptop handle laptop battery charging repair

There are two types of mechanisms used in the laptop battery charging repair section.

  1. Buck Converter
  2. Buck-Boost Converter

Let’s see them one by one.

 

1. Buck Converter :

Single-phase synchronous converter and has the same working. This consists of a mechanism in which one high side MOSFET and one low side MOSFET turns on-off alternatively to turn down the voltage from 19v to 12.6v which is necessary for a laptop battery.

 

2. Buck-Boost Converter :

There is a use of the first set of high-side and low-side MOSFETs which comes before the inductor. They can also work as a regular buck converter.

After it, there is a second set of MOSFETs which is used to boost the voltage coming from the AC adapter.

The main disadvantage is that it takes 5v to 20v to charge the battery. Which makes it very slow to charge the laptop.

 

Battery voltages in the cell of the laptop

Lilium cells make laptop batteries. These can be made up of either Li-ion cells which are like cylindrical shapes or LiPo cells which are flat rectangular.

The voltages of these change according to the brand of laptops. Typically Li-ion has a voltage of 3.6 to 3.7v. LiPo cells typically have voltage around 3.7v to 3.85v.

 

Troubleshooting charging circuit

1. No Power :

The first thing you will check is whether the main power rail in a laptop is present or not. If it’s present that means the problem is not present in the charging circuit. You can still check any short MOSFET for DC supply or changing ic having missing voltages. Because in some cases they can be root or trouble too.

Before it, you have to check you have HPB or an NVDC configuration. With HPB configuration you have to check the voltage after the second DC-in MOSFET. You have to find AC adapter voltage.

In the NVDC connection, you have to check voltages after the buck convertor coil and also after the fuse if it exists in that laptop model for location.

If the found fuse is burnt via checking before its voltage and after its voltage. Replace it and go to the next section for ‘short gound on the main rail’. resolve it before applying power.

 

2. Shorted DC-in MOSFET

There is also one issue that is very common. The issue is mostly faced by newbies in this field. There is a difference between MOSFET blocking the current and *failed*.

In the HPB technology method there can be the case that the main power rail will be present as the current will pass from within shorted MOSFET but there can be a possibility that some signals from charger IC may be missing which makes our platform unable to run.

Whereas in NVDC the main power rail may be missing. Check the resistance between the Drain/Source/Gate of both DC in the section for whether they are shorted or not. The resistance should be at least a few kilo-ohms.

 

3. There are burn-in current sensing lines in the laptop battery charging repair section

The overcurrent from battery adapter to battery gets monitored by charging IC. There can be burned in the current sensing circuit either in current sensing sensors or resisters that connect them to current sensing amplifiers. The easy way is to measure the resistance at the current sensing amplifier pin of the charger IC. The measured resister should be a summation of the current sensing resistor and resisters which connect them to IC.

This also takes care of any possible break of line that was happened due to any liquid damage.

 

4. Missing voltages on charging IC in laptop battery charging repair section

There are some voltages that are required to run the charging IC. The names can be vary depending upon the charger IC brand. But majorly,

  1. DCIN/VCC – Mostly it is close to the AC adapter. These are voltages coming from the AC adapter.
  2. ACIN/ACDET – Mostly it is required a voltage of more than 2.4v or 2.6v. It is dependent on charger IC and it uses the voltage divider to get the current-voltage range.
  3. REGN/VDD – It has internal LDO output mostly between 5v to 6v. The input for this output is taken from DCIN/VCC.

The following signals should come after coming previous signals.

  1. ACOK  – It denotes the input voltage is good. In the case of P-type MOSFETS, it drives MOSFET gates directly.
  2. ACDRV – Only present in the n-channel type of MOSFETs. Mostly cases it is around 25v voltage which should minimum of more than 6v.

5. Damaged Passive Component in laptop battery charging repair section

By doing a visual inspection we can spot any damaged capacitor or missing/damaged resister in the circuit. This comes mostly in cases of liquid damage but rarely in other cases. You can follow visual hints if you know or found that there is liquid damage.

One of the issues can be gate resisters for DC-in MOSFET, which could be near it. You can always them for precaution.

 

6. Dead charger IC in laptop battery charging repair section

If you go by all previous issues then the issue might be that the IC itself is dead. Check for its behavior change by replacing it.

 

7. Battery not charging in laptop battery charging repair section

Try multiple batteries. The problems can be the battery itself for the battery not charging. Change the battery until you found the right one. because the market is filled with garbage quality batteries.  99% of problems can be due to batteries. While some new batteries are required to ‘kick-start’ via plug-in the adapter, some come filled in with 50%, 80%, or in some cases 20% too. It is important for you to know whether you have HPB or NVDC in your circuit. Your battery should start charging 100%.

 

8. Battery not detected

There can be an issue with the charging circuit SM-Bus. Check all voltage modes and SM bus to the ground on SMBus SDA and SCL lines.

 

9. Low voltage on battery charging rails

In the case of NVDC technology if on battery charging rail there is too low voltage present the battery will not start to charge. Thye gate resister of MOSFET or MOSFET itself which is situated between buck convertor output and better power rail can be problematic. Inspect it and change it if it’s found faulty.

In HSB topology battery is most connected to the buck convertor directly. The bad battery or deeply discharged battery will pull down output. One way is to let the battery charge overnight, if this does not solve the problem then replace the battery. Without the battery, the output within the output rail will be low. DC-in MOSFET or Current sensing can be a problem in this situation.

In some chargers, ic’s the ic have a ‘CELL’ pin to control the voltages applied to batteries relative to the number of cells in series in the battery.  The wrong setting in ic can cause wrong output.

 

10. High voltage on battery charging rail in laptop battery charging repair

Shorted high side MOSFET with buck convertor on charging rail can be also caused for it. Shorted battery to system MOSFET can be problematic in HPB technology.

 

 

 

 

You can also check our other laptop preparing help guides.

 

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www.lqv77.com alternative free schematic

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lqc schematics free alternative over 30000

Follow are some alternative sites to get laptop schematics free sites like lqv77. Below are alternative sites to get laptop schematics free sites like www.lqv77.com schematic.

For further details about laptop schematics, you can also check for a good resource like Wikipedia for laptop repair

What Do the Laptop Schematics Give

schematics are basically graphical representations of motherboard components and various parts in them. It is most available in .pdf format. They consist of components and wiring within the motherboard.

Any newbie (new technician) in laptop chip level repair must use laptop schematics. They are very useful for tracing the circuit of the laptop motherboard.

How To Read Schematics?

The reading is simple. Let start with the starting point which is the VIN pin and go until the last point which is the CPU for the laptop. Any voltage drop can be the root cause of the laptop’s dead condition.

Coming back to the topic of how to read laptop schematics which can be done via getting block diagrams of laptops given on the laptop schematics.

Also, there are components present over the motherboard also present over schematics. You can trace it from there too. There are also some ic like

  1. lan ic
  2. volt-in ic
  3. step down ic
  4. ram ic, etc

Laptop schematics play an important role when repairing any laptop.

When to use laptop schematics?

Laptop motherboard schematic diagrams can be extremely helpful when it comes to repairs. Having a clear and concise diagram can make all the difference in being able to properly fix a problem. We can take help from lqv77 similar free websites for schematics as we have provided.www lqv77 com also provides schematics but we provide a free alternative which provides www.lqv77.com with a similar schematic in english language. Most are downloadable pdf format diagrams for laptop motherboard.

Laptop motherboard schematic diagrams can be extremely helpful when it comes to repairing your computer. By having a visual guide, you can more easily identify and fix problem areas. These diagrams can be found online or in repair manuals.

laptop motherboard schematic diagrams for repairs. Sometimes it is impossible to show hardware problems online for a solution. we do use lqv77 similar free sites schematics for getting information problems. We use the laptop motherboard schematics free / paid sites to troubleshoot the core problem. We also provide bios similar to lqv77.

What Are Laptop Schematics?

Laptop schematics are diagrams in pdf formats that are used to denote the process flow in a laptop. Any kind of laptop has schematics (almost 98% of laptops have). Apart from the board views which most of today’s laptops don’t have. We can get it from free laptop schematics sites. 

The flow starts from the VIN pin which injects voltage into the laptop. The voltage at this point may vary from 18 volts to 20 volts. There are different laptop SMD and Non-SMD components present on the schematics. There are different components like capacitors, diodes, resistors, crystals, coils (aka inductors), transformers, transistors, MOSFETs.

Why use schematics?

Schematics used for systematic flow findings in laptop motherboard. Without schematics, someone can only guess the error, which can also result in the loss of that component. That method of guessing was less efficient than schematics tracing. There are two types of tests you can conduct using schematics.

There are different types of testing used for troubleshooting desktop or laptop motherboards. You can use it according to your need. But cold testing from them can be done using schematics.

When we think of the best site for laptop schematics we think about sites like lqv77.com. But there are many similar sites that are available free of cost for downloading schematics and even the bios and boardviews.

The Solution

Our displaymonk.com site provides the best schematics bios and boardviews free of cost. You don’t need to create an account or anything. Just download your file it’s easy like that. You can get them by searching in the bar below. we provide www lqv77 com similar schematic free of cost.

Download all important as require schematics for free to get used to them either for education or troubleshooting motherboard problems.

working over 30000 schematics of laptops desktops
working over 30000 schematics of laptops desktops
Website Name Description
https://displaymonk.com/free-download-laptop-desktop-schematics/ all kind of free schematics, bios and boardviews are free available.
http://www.hrimafix.com laptop schematics and BIOS Chinese site.
http://www.vinafix.vn premium and bios paysite. you will find mostly schematics here.
https://www.alisaler.com/ this one also provides schematics. they have a huge collection.
http://www.laboneinside.com/laptop-schematic-diagram schematic diagrams will be provided here
https://bios-pw.org/# bios password recover all laptops available
http://www.badcaps.net/forus/index.php repair forum and diagrams available
http://www.s-manuals.com laptop motherboard schematics available here
http://www.ja.axxs.net/ IBM bios password NVRAM location
http://notebook1.ru/forma1/viewforum.php?f=50 the laptop bios Russian site is here
http://laptopsvc.vn/vi/bios/2013/07/81E21021/bios-acer/ a wide variety of schematics and bios are available here
http://onns.ru/category/Asus/ Asus laptop schematics
http://www.chinafix.com this is a good Chinese site for schematic diagrams and bios bin file
http://biosflash.com/index.htm This provides bios bin file for desktop motherboards
https://www.cpubenchmark.net/laptop.html This site is very useful for finding all CPU’s efficiency and identification.
http://www.cpu-world.com cpuworld website provides CPU identification
http://biospassword.eu/free this site provides bios password recovery
http://www.notebookreparingguide.com/ this site consists of a directory of sites with laptop tech support
http://www.ifixit.com/Guide/ This site provides information on repairing including Apple devices, iBooks/MacBooks, and desktop models.
http://repair4laptop.org/ This is a site dedicated to owner-made repair guides and mods.
http://laptop-schematics.com Great site for free laptop schematics
http://repairalaptop.com It gives repair related information. Also it offers laptop schematics.
http://alisaler.com Alisaler is a brand name in part of laptop shcemtics which has been operating from many years.
http://schematic-x.blogspot This is blog which provides the laptop schematics
http://laptopschematic.com This site also provide laptop schematic
http://nehruplacestoreindia.com This site mainly proivde laptop reparing parts but they also provide few schematics as new section in site.

Final Solution

You can download all important as require schematics for free to get used to them either for education or troubleshooting motherboard problems.

You can also check our other laptop preparing help guides

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Dell Laptop Beeps Codes

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There can be the case when laptop chip level repair person needs information on dell laptop is not working. It can be gte from the beep code produced by the Dell laptop. These dell laptop beeps codes are given below:

Dell laptop beeps codes and their solutions are  given below:

One – Possible system board failure or BIOS ROM checksum failure

Two – No RAM detected

Three – Possible system board failure or Chipset error

Four – RAM read/write failure

Five – Real Time Clock failure

Six – Video card or chip failure

Seven – Processor failure

Eight – Display failure

For more visit: Dell.com

You can also check our other ICs in laptop motherboard guides.

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