All laptops have a video card; other common terms for the video card are ?graphics card? or ?GPU? (graphics processing unit), graphics ?chipset? or ?video chip?. The ?video chip? is integrated on the motherboard, and the ?video card? is proprietary in that it connects to the motherboard using a ZIF slot (zero insertion force) then secured by screws.
A video card or chip will fail mainly due to thermal breakdown. The most likely reason for this breakdown is overheating of the laptop. Overheating happens when the fan and heat-sink assembly become clogged. A heat-sink is typically a metal mix/blend, mainly being copper. It is also fragile. You do not want to bend or flex the heat pipe of the heat-sink or you will increase the chance of overheating due to incorrect motherboard thermal temperature readings. The end of the heat-sink will have ?radiator? fins attached to the heat pipe end. These metal/copper fins aid in the cooling and heat dissipation by pushing the heat to the pipe end and then carrying it through the fins and out the exhaust port.
Dust and debris can build up… Similar to a laundry dryer’s lint trap that you remove and empty… except the laptop doesn’t allow one to easily clean this without complete disassembly of the laptop. A toothbrush is used to clean between the fins of the heat-sink, remove all dust and debris from the heatsink. You will then need to unscrew or un-brace the fan from the heat-sink to properly clean the fan. These will be micro sized screws typically 4 of them and some might be hidden under plastic stickers.
Separate the fan lid from the fan base to clean. Most fans will be magnetic not ball bearing, and you will be able to pull the fan blade off of the fan base to clean it. Run the toothbrush in between the fan blades from the top side and bottom sides of the fan. It is a good idea to also use a paper towel or similar (I will spray glass cleaner on it, then fold it a bunch of times to make it thicker, then run the wet towel in between the fan blades) to better clean it, also cleaning the base of the fan housing. Reassemble the fan and reattach it to the heat-sink. Reapply any thermal paste to the heat-sink’s cooling pads if needed.
If you plan on adding thermal paste to the heat-sink, First, It absolutely must be Silver Thermal Paste, not Ceramic (silver in color, not white or pink in color). Also, you absolutely must remove any remaining ?old? thermal paste from both the HeatSink and the Chip or CPU it is covering. To remove old paste, use denatured alcohol on a paper towel, rub away. If the old paste is real thick and crusty, use a guitar pick or flat plastic card or tool to gently scrape away the paste. Important here not to gouge the heat-sink thermal plate if you are scraping the paste away… that is why you would use plastic to remove it, or just a paper towel.
When applying thermal paste, you do not ?glob? it on… You should apply a very small dot at each corner and a couple in the center, use a guitar pick or similar to smooth out the paste so there are no dips or pits.
The CPU will always use thermal paste because it does not get as hot as the GPU does. The GPU will almost always use a thermal pad and not paste. Thermal pads will allow for the natural thermal expansion of the chipset and will allow for the greatest heat dissipation. Do not replace the thermal pad with a copper shim on a NVidia chipset… You must re-use the thermal pad on the video chip.
Okay, now back to the GPU and why/how it can cause Power Issues with the laptop.
Typically a motherboard will have a Northbridge chipset, a Southbridge chipset and a GPU chipset (3 Separate IC Chips), though the need for smaller and thinner laptops has led to newer technology parts and components. A lot of laptops will integrate the Southbridge chipset and the GPU into one IC chip. A good example is the HP DV series, which mainly used an AMD/NVidia or Intel/ATI Chipset. The AMD/NVidia IC would use integrated Southbridge/GPU on about half of the models released. If the heat-sink only has one additional cooling thermal pad (besides the CPU pad), then chances are the GPU and Southbridge chipsets are integrated. If the heat-sink has 2 additional thermal cooling pads, the one closest to the CPU would be the GPU and the furthest is typically the Southbridge chipset. The Northbridge does not produce heat.
The CPU is one of the most stable components in a laptop and there will be no need to discuss any repair to that part in this book. They can “fail” though and if a replacement CPU is readily available, you can try exchanging just to rule out the CPU. But chances are, it is not the CPU that is causing the issue (unless you installed an incompatible one).
The GPU connects to the motherboard using a BGA (ball grid array) connection; this is a connection that does not allow for physical removal of the chip without special equipment (rework machine or similar)
As opposed to a ZIFF socket CPU where instead of solder ball – to contact pad connection, you have pins protruding from the CPU and fitting into the matching pattern on the ZIFF CPU dock.
Thermal Over-Exposure is what creates failures in the BGA connection grid of the GPU (video chip). The heat combined withsome GPUs using incorrect solder; will break down the solder ball contact connection over time and over prolonged exposure to overheating conditions (clogged fan/heat-sink).
I will take a minute here to Explain Hot Air Reflowing and Debunk the Myths Surrounding the use of Hot Air as opposed to Infrared.
Use of a ?Hot Air? gun, if done right, will work exactly as a rework machine. After all, it is the same exact setup as a rework machine except for the PCB braces, temperature dials and the metal supporting arm to hold the heat source.
YouTube has given the whole Reflow process a ?bad? name due to the knuckleheads using hairdryers, torches, Bunsen burners, candles and so on… Even the ones using heat guns…
All they know is that they’re waving heat at the chip; yet have no clue why or exactly how… No wonder they’re blowing up their machines and their repairs only last a week…
There are differences between the use of infrared and hot air, though the average person will not be able to obtain or afford an expensive infrared rework machine, which is why this book will teach you the Professional Reflowing Hot Air Method, For Use on Any and All Video Chipsets. Infrared will transfer heat without overheating the surrounding areas; it is more constant source of heat and will penetrate the PCB / ICs more rapidly. Though with the right heat gun and the right instructions, hot air can and will obtain similar results. Infrared is recommended for Reballing and replacing the GPU, but for reflowing (what is taught here), Hot Air is not only more cost efficient, convenient and cost effective.
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