#0026: Preventative maintenance for laptop computers

Otto

#0026: Preventative maintenance for laptop computers

Preamble

This will be a brief guide to maintaining the hardware of a laptop computer. This is with the intent to prevent the breakdowns and computational performance loss, that is resultant of extended user negligence. It is pretty much a cleaning guide, including: necessary tools, materials, tests, parts descriptions, general methodology, and background information. This is provided with the aim to bring unmaintained units into a workable state. Although I specify this guide for laptops, most of the techniques discussed can apply to any computer. This includes: desktop PCs, game consoles, or servers. The core ideas discussed here have more-or-less universal application.

What causes negligence related breakdowns?

The short answer is that this type of breakdown, is caused by the overheating and eventual burnout of computer components. This overheating is due to the diminishing effectiveness of the machine’s cooling system over time. Although a laptop’s cooling system consists of several contiguous parts, there are only three main parts that require any degree of special attention. These are: the heatsink fins, the fan, and the thermal transfer material (thermal pads/paste).

Where is heat created within a computer?

Although technically most semiconductors can create heat when operating, there are only a few components that create enough heat to warrant the use of a cooling apparatus. These include: the CPU (Central Processing Unit), the GPU (Graphics Processing Unit), and in high power systems, this even includes the voltage regulator modules that supply these processing units.

It should be noted that any given laptop’s cooling system is already configured to attach to all the components that actually need cooling. It was configured to do so at the designed stage of product manufacture. So there is no sense in worrying about the heat output of any components that aren’t covered by the default cooling system that the laptop already has.

Laptop cooling system explained

Cooling plate: This is the initial heatsink that conducts heat out from the chips and into the heat pipes.

Heat pipes: Heat pipes are good at transferring heat from one end of the pipe to the other quickly. They do this by being filled with a liquid that evaporates and condenses readily within the pipe’s sealed system. The general idea here is that the liquid evaporates into gas on the hot side, causing it to quickly travel to the cooler side where it condenses back into liquid as it loses it’s energy to the surrounding material.

Heatsink: Heatsinks have fins that are designed to have as much surface area as possible between metal and air. This is to facilitate the convection of heat out of the cooling system and into the environment.

Blower fan: The blower fan is exactly that. It blows the hot air that the heatsink fins have warmed up, out and away from the computer. This is to maintain a constant temperature gradient, that facilitates heat energy moving out of the heatsink fins.

Why is maintaining a cooling system especially important in laptops?

The main reason why maintaining the cooling system is especially important within laptop computers over for example desktop computers, is that often the cooling system on a laptop is barely adequate for it’s computer’s needs as it is; bran new. As such, any additional degeneration in cooler system efficiency may quickly effect performance. The reason why many cooling systems can barely dissipate the heat produced by their onboard CPU and GPU is two fold.

One, laptops have a significant size limitation that desktop computers do not have. Every component that would go into a typical desktop computer, has to fit into the significantly smaller profile of a laptop. This unfortunately includes the cooling system, whose effectiveness directly correlates with size. Bigger heatsinks, sink more heat; more heat pipes, can move more heat concurrently; and bigger fans move more air. It is as simple as that. Additionally, the current market trend of making laptops thinner and lighter is exacerbating this issue.

Two, the role of the modern laptop is different than what it once was. Modern laptops have higher power requirements than ever before. This is due to them housing more powerful CPUs then ever before. CPUs which generate more heat than ever before, heat which needs to be dissipated.

Modern laptop computers have moved beyond the realm of earlier notebooks; i.e. machines designed for web browsing and clerical work. With the introduction of gaming laptops and desktop replacements, we now high performance machines; genuine portable alternatives to full desktop computers. Many of which housing CPUs comparable with their desktop counterparts. The only unfortunate part is that they don’t have the same level of cooling available. Therefore maintaining the efficacy of the cooling system that is does have is that much more important because of that.

Example of a laptop with an underdeveloped cooling system

I have in my possession a Toshiba Satellite P850 that I purchased new around 2012. This particular machine came with a socketed CPU (i.e. replaceable), and at the time of purchase I recall having to specify whether I wanted an Intel i3, i5, or i7 CPU installed. Three very different CPUs in terms of computational ability and heat output. Yet the rest of the computer was of the same design, including the built-in cooling system. I purchased the most powerful i7 package option, and consequently have always had heat related issues with the machine; having to even augment the built in cooling system with an external “laptop cooler pad” to avoid overheating when under extended loads (e.g. playing video games).

post maintenance temperature statistics for Toshiba Satellite P850 laptop (note: bottom two temps are irrelevant as they are HDDs)

Symptoms and explanations of laptops with poor cooling

Symptom list:

  • The machine is generally dirty.
  • Heatsink fins blocked up with dust, grease, food, or grime.
  • Loud fan: fan operating constantly on full throttle.
  • Fan notably vibrating or making clicking noises.
  • Fan not spinning freely (i.e. noticeably struggling to spin).
  • No fan noise at all.
  • High localised radiant heat.
  • Drop in CPU performance when under load.
  • Diagnostic software reading high operating temperatures at idle state.
  • No thermal paste present between the cooling plate and CPU.
  • Dry or hard thermal paste present between the cooling plate and CPU.

Explanations:

  • The machine is generally dirty.

If on a basic visual inspection the machine is externally dirty, it is likely to be in a similar state internally. Since dirt and dust are generally good thermal insulators, they’ll assist the machine in retaining unwanted heat energy. Additionally, general cleanliness is also a good indicator as to the level of maintenance the computer has been subjected to.

  • Heatsink fins blocked up with dust, grease, food, or grime.

Heatsinks require large surface areas, in order to transfer heat energy effectively from themselves and into the immediate local environment. In this case: air. This is done via a process called thermal convection. Heatsinks achieve their large surface area (relative to mass) by employing heat-fins. Row upon row, of often wafer thin plates that maximise the heatsink’s contact with the air around it.

In order for the heat exchange process to operate effectively: air must be allowed to move freely between the heatsink’s fins and contact it’s surfaces without obstruction. Additionally, the constant movement and renewal of the air through the heat fins maintains a thermal gradient that keeps heat energy moving out of the heatsink and into the local air. If airflow is blocked for whatever reason. Then sooner or later, the heatsink will reach a level of thermal equilibrium with the local pocket of air around it, at which point no more heat transfer will occur.

  • Loud fan: fan operating constantly on full throttle.

During normal operation, a computer will modulate the revolutions of it’s cooling fan(s) in order to maintain a stable system temperature. This modulation includes: raising the fan rev speed to decrease temperatures when necessary, and lowering fan rev speed to reduce fan noise once safe temperatures have been achieved. If the computer fan is spinning loudly at full rev continuously, it is indicative of the system sensing the presence of a consistently high temperature.

  • Fan notably vibrating or making clicking noises.

Fans vibrating or making clicking noises is a possible indicator of an issue with the fan bearings. Such as misaligned or dry bearings. This generally makes the fan spin slower than intended, or suddenly stop for a period of time, before resuming spinning as before.

This issue is twofold. One, that fan will not be able to adjust it’s rev speed to match the system’s needs in time. This is due to the unaccounted for resistance to rotation that it will encounter in it’s current state. Two, when it does spin, it risks getting stuck perhaps permanently. When electric motors like the one in these types of fans get stuck, they take more and more electric current. If it doesn’t start spinning soon, it risks overheating the motor coils and burning itself out.

A clicking fan needs to be removed, disassembled, then inspected. If it’s bearings are merely dry, then they can be re-lubricated. The fan may work fine after this. If however the bearings are damaged, then either they’ll have to replaced; or alternatively: you may have better luck simply replacing the whole fan assembly. Additionally, a strictly vibrating fan will also have to be disassembled and inspected. In this case: look for anything that may make it spin off kilter, such as a bent or misaligned central shaft or blade hub.

  • Fan not spinning freely (i.e. noticeably struggling to spin).

A sticky motor struggling to spin could be caused by anything; from hair or dust wrapped around or caked onto the central shaft of the electric motor, to the fan bearings drying out. Since a stuck motor pulls more current than a spinning motor, it also generates more heat. This heat will eventually destroy the motor. Clean the fan thoroughly and test it. If it still struggles to spin. Then disassemble it for inspection.

  • No fan noise at all.

If you have no fan noise what so ever, then chances are that the fan isn’t spinning at all. Check that it isn’t stuck, or burnt out. It should be noted that: a laptop’s cooling system needs an active air current running through it to remove the residual heat. The passive cooling components alone are often not sufficient to dissipate the heat, at least without having something to actually expel that heat from the system. With that in mind, replace or repair the fan as soon as possible.

  • High localised radiant heat.

High localised radiant heat near the source indicates that the heat isn’t being dissipated from the source quick enough. I.e. there is likely a break somewhere within the cooling system that prevents the heat energy from travelling away from the source.

  • Drop in CPU performance when under load.

Many CPUs or systems, have a thermal throttling feature where they actively limit the processing capabilities of the CPU. This is in order to limit it’s resultant heat output. Usually machines don’t limit their CPU performances in this way, unless the cooling system is proven inadequate. In order for a CPU to start thermal throttling, it needs to reach a threshold temperature that is considered potentially dangerous to the CPU itself.

  • Diagnostic software reading high operating temperatures at idle state.

Diagnostic software like Speccy and Psensor can be used to display information from the built-in system temperature sensors. Assuming an ambient temperature of approximately 20 degrees celsius: CPU temperature readings above 60-70 degrees celsius on an idle system is indicative of a poor cooling system. Additionally when the system is actually under load (i.e. doing work), these temperatures can spike to 80-90 degrees. Reaching the thermal throttling thresholds.

  • No thermal paste present between the cooling plate and CPU.

Thermal paste is a heat conductive layer between the CPU and the cooling plate (or heat sink). It is necessary to enable the most efficient conductive transfer of heat possible out of the CPU and into the cooling system. Although technically, computers can operate without thermal paste. It is not recommended, especially in higher wattage systems with more powerful CPUs. CPUs which can reach very high temperatures very quickly.

You could probably get away with not using any thermal paste on a really low power system. For example with my 2009 HP Mini 110 laptop, which has an intel atom processor inside it. Since that CPU can’t really generate enough heat to be concern. Still I wouldn’t recommend it. Now that I think about it: the only real time I ever came across a machine without any thermal paste applied, was when I purchased a “seller refurbished” unit. I.e. basically due to human error.

  • Dry or hard thermal paste present between the cooling plate and CPU.

As thermal paste ages it many become: hard, dry, and brittle where it was once a pliable soft paste. This new state means that it can no longer do it’s role of filling in the miniscule gaps between the cooling plate (heatsink) and the CPU. It also diminishes it’s effectiveness at conducting heat, due to the air gaps it likely to develop as it dries out.

Tooling

This is a small list of tools and optional alternatives to the one listed above it.

Tools:

  • clean cloth
  • bristly brush (nylon paintbrush)
  • (optional) vacuum cleaner
  • (optional) compressed air

Materials:

  • cotton earbuds
  • (optional) tissue paper
  • isopropyl alcohol
  • (optional) alcohol wipes
  • (optional) rubbing alcohol
  • thermal pads

Maintenance

Summary:

  • replace thermal paste if it is dry or contaminated with anything (e.g. dirt)
  • replace (or clean) any thermal pads that my be contaminated
  • clean out the heatsink fins with a brush
  • clean out the fan with a brush
  • make sure the fan spins freely

Specifics:

Cleaning off thermal paste

Thermal past is easy enough to remove. All you need is a tissue or an earbud dipped in isopropyl alcohol. Just carefully wipe all the residue off. Then give a final pass to make sure you remove any errant cotton/tissue fibres.

Cleaning thermal pads

Sometimes you may come across thermal pads on certain secondary chipsets around the cooling plate. These pads may be of various thickness to cover the variable gaps between the chips’ height and the cooler plate above it. Because of this it may be somewhat difficult to find appropriate replacement thermal pads.

In this case cleaning and reusing the stock thermal pads is a decent alternative. A good wiping down with an alcohol soaked tissue to remove any dust and foreign debris on the stock pads is sufficient to reuse it. Since traditionally thermal pads (especially the thicker pads) are used for chips that although produce heat, they don’t produce enough to warrant special attention. As such getting a fresh replacement for each chip is not critical.

Cleaning out heatsink fins

Using a stiff paintbrush, wipe out all the dust and debris by following the lines of the fins. With heat-fin tunnels, if they are short: stab the bristles of the paintbrush into it at both openings. Otherwise you may require air to clean long tunnels properly. Either use compressed air or a vacuum cleaner to blow or suck the dust out respectively.

If however the heatsink fin tunnels are blocked up with something sticky, like grease or dried residue from a sugary drink. Then actually immersing the entire heatsink in warm soapy water and washing it will be necessary. Just make sure it is absolutely dry before putting it back into the machine.

Applying new thermal paste

Generally I find that users need less thermal paste than what they may initially think. All you need for thermal paste is to have enough to sandwich between the cooling plate and the CPU die. All thermal paste does is smooth out the imperfections within the cooler plate surface, and fill in the small gaps between the plate/heatsink and the CPU. It does so to maximise thermal conduction by reducing the effect of the barriers between the materials. That’s all.

I find that about a pea sized amount for an average sized CPU is good enough. I also like to use a spreader to make sure that all the corners of the CPU die are adequately covered, before I mount the heatsink on. Although putting on too much paste (within reason) doesn’t really affect performance or anything. It just squeezes out from between the cooler plate and CPU, as it is tightened on.

Closing thoughts

I am genuinely surprised that I managed to write so much for what could adequately be summed up with two sentences: “Clean the damn thing! It’ll live longer.” However I think that an actual breakdown and identification of the types of faults that a laptop could develop if left uncared for, and why preventative maintenance for laptop computers is especially important: is what really gives this article some value. I hope it makes average users, regardless of skill level understand the importance of preventative maintenance and recognise some of the symptoms of when it is time to open up their computer and give it a good clean and freshening up.

Probably the biggest hurdle I think the average user would have is applying new thermal paste to a CPU. If you are in anyway daunted by the process, just keep these points in mind. One, CPUs are not made of glass (or are they?), they aren’t that fragile. Just be careful, move mindfully, and you likely won’t damage it. Also it’s good protocol to ground your hands before handling sensitive electronics. Something as simple as touching a metal chassis of a plugged in appliance would do it. This is to help prevent any electro-static discharge.

Two. Thermal paste is not expensive, don’t be afraid to “waste” some practising applying it elsewhere. Also thermal pastes are all pretty much the same stuff. Don’t worry about brand differences. Chances are you are not overclocking, so you don’t need to worry about the specialist materials like liquid metal, or the performance differences between various expensive named brand pastes. Just buy whatever you can get in your budget, and use that. It’ll do the job.

Ultimately, there really is no excuse for not cleaning your machines. Remember: take care of your tools, and they’ll be around to take care of you.

Thank you for reading.

Links, references, and further reading.

https://en.wikipedia.org/wiki/Fin_(extended_surface)
https://en.wikipedia.org/wiki/Heat_sink
https://en.wikipedia.org/wiki/Convection
https://en.wikipedia.org/wiki/Convection_(heat_transfer)
https://en.wikipedia.org/wiki/Thermal_conduction
https://en.wikipedia.org/wiki/Semiconductor
https://www.pcgamer.com/this-detailed-breakdown-of-a-high-end-motherboard-is-pretty-awesome/
https://www.tomshardware.com/reviews/vrm-voltage-regulator-module-definition,5771.html
https://www.maketecheasier.com/what-is-vapor-chamber-cooling/
http://www.nuclear-power.net/wp-content/uploads/2017/11/Convection-Convective-Heat-Transfer-comparison-min.png