Why don't PC builders properly torque their screws when mounting motherboards and heat sinks?

[SportingKC]

I have a background in gunsmithing and the cardinal rule for us is nothing gets screwed in or tightened without using a torque screw driver and precise pound per inch to ensure optimal (consistent) performance. 

 

Why don't PC builders follow similar canons? PCs experience various temperatures, are occasionally moved around, and contain dozens of fragile parts. To me, these are all reasons why properly mounting and torquing your motherboard, heat sink, and other components to a precise pound per inch is critical. But all I ever see is advice to "tighten things fairly tight, but not too tight," which drives me crazy because it's like someone defining a word with a word. 

[DildorTheDecent]

2 minutes ago, SportingKC said:

I have a background in gunsmithing and the cardinal rule for us is nothing gets screwed in or tightened without using a torque screw driver and precise pound per inch to ensure optimal (consistent) performance. 

 

Why don't PC builders follow similar canons? PCs experience various temperatures, are occasionally moved around, and contain dozens of fragile parts. To me, these are all reasons why properly mounting and torquing your motherboard, heat sink, and other components to a precise pound per inch is critical. But all I ever see is advice to "tighten things fairly tight, but not too tight," which drives me crazy because it's like someone defining a word with a word. 

Because that's just silly. 

[NinJake]

Because a gun has the ability to kill, repairing/cleaning improperly can result in greater damage to the user or those around.

 

A computer just needs to work. If it doesn't work, at least nothing explodes or no one gets shot. (Go back and refasten the screw) It's pretty hard to not screw in something correctly though.

[ProjectBox153]

It's because there is no reason to be precise. You can sit a heatsink on a CPU socket and it will work. "Tight enough but not too tight" is the easiest way to screw something in because it doesn't have to be precise. Computers aren't that sensitive, unless you just sit the screws in the holes and don't tighten them at all. 

[thenastyjbenny]

I'm all ears as to how you'll change the PC world. 

 

You think I'm kidding?

 

Make a video about it. I'll listen. I'll even buy the tools if you explain it well enough. 

 

Convince me.

[Kinda Bottlenecked]

That means I'll need spend more money on equipment to get that 0.5*C difference in temps

[Technous285]

The typical maxim is basically "If you KNOW you've got it tightened down all the way - that's too much and back off a touch".

 

Seriously, if you tightened down the screws on a heatsink using a torque screwdriver to the point where it can't go down any further? You're likely to damage if not kill the chip under the heatsink and/or the PCB around the chip.

Most CPU heatsinks nowadays (including waterblocks from like EKWB) have thumbscrews so you tighten them down as far as you can without a screwdriver then maybe add a 1/8th or 1/4 turn with the screwdriver in order to minimise the chance of damaging the chip under the heatsink/waterblock.

[stefanDB]

the only reason not to overtighten the screws is that you don't want it to break, but that wont happen often, and as long as the screw isn't going to come loose it will be no issue at all. you have a very large margin to work with, which makes it easy to do without precise tools.

[linustouchtips]

my rule of thumb is never to screw to hard sometimes it works out(dam kids). 

[stefanDB]

1 minute ago, Pohernori said:

That means I'll need spend more money on equipment to get that 0.5*C difference in temps

I don't even see why the temps would improve at all, the only time I would do it is if the PC moves or vibrates a lot to make sure it won't get loose

[SportingKC]

2 minutes ago, Technous285 said:

The typical maxim is basically "If you KNOW you've got it tightened down all the way - that's too much and back off a touch".

 

Seriously, if you tightened down the screws on a heatsink using a torque screwdriver to the point where it can't go down any further? You're likely to damage if not kill the chip under the heatsink and/or the PCB around the chip.

But if you properly torque it to a specific pound to inch then you'll never have to worry about something being too tight or too lose. It would also guarantee everything is precisely level and even distribution of thermal compound. I imagine it would also decrease the noise output of the entire machine by evenly distributing vibrations - but this is all theory, not tested. 

[Mira Yurizaki]

21 minutes ago, SportingKC said:

I have a background in gunsmithing and the cardinal rule for us is nothing gets screwed in or tightened without using a torque screw driver and precise pound per inch to ensure optimal (consistent) performance. 

 

Why don't PC builders follow similar canons? PCs experience various temperatures, are occasionally moved around, and contain dozens of fragile parts. To me, these are all reasons why properly mounting and torquing your motherboard, heat sink, and other components to a precise pound per inch is critical. But all I ever see is advice to "tighten things fairly tight, but not too tight," which drives me crazy because it's like someone defining a word with a word. 

Because PCs aren't expected to survive tens of thousands of sudden shocks all the time.

 

Also being too tight means that there's no room for thermal expansion.

Edited May 2, 2017 by M.Yurizaki
Probably doesn't really matter

[OddsCrazyStuff]

Besides things already mentioned, so does a lot of PC parts have soft metals, like copper or aluminium. Meaning its easy to strip the screws and/or the hole, which will suck in the long rung.

[Alexei Drekker]

All the sensitive components are already screwed in and calibrated or are not user serviceable. Most people building their own PCs only mix and match stuff. Like lego blocks or puzzle pieces, albeit with slightly more complicated compatibility criteria. A gun, on the other hand, has all these precision components that need to be calibrated to that degree so that it does not lose accuracy or explode in your face. I am not a gunsmith, so I can't speak too much about it.

[Cyracus]

34 minutes ago, SportingKC said:

Why don't PC builders follow similar canons?

because you don't need to, screw it down until it's held down, there are no massive shocks, well, maybe if you drop your computer, but then you end up screwed whether you're tight or super tight so... anyway no regular massive shocks to loosen and back out the screws so you don't need to torque things down in the first place

[TVwazhere]

39 minutes ago, SportingKC said:

I have a background in gunsmithing and the cardinal rule for us is nothing gets screwed in or tightened without using a torque screw driver and precise pound per inch to ensure optimal (consistent) performance. 

 

Why don't PC builders follow similar canons? PCs experience various temperatures, are occasionally moved around, and contain dozens of fragile parts. To me, these are all reasons why properly mounting and torquing your motherboard, heat sink, and other components to a precise pound per inch is critical. But all I ever see is advice to "tighten things fairly tight, but not too tight," which drives me crazy because it's like someone defining a word with a word. 

Because the performance of a PC does not come down to tightness of the screw. 

 

If i leave two thumbscrews on my gpu loose, i wont lose 10% performance in games. If my CPU cooler has one screw thats not all thre way in, im not going to see a difference in overclocking potential. 

 

Other than fans and Hard drives (occasionally ODD's) there are no moving parts. Nothing to vibrate, nothing takes load, nothing experiences force. Guns (and more namely to relate to regular every day people, car tires) experience varying load constantly, and must be set to a specific pressure to best cope with said varying loads. Too tight and your gun blows up. Too loose and a wheel falls off. Your motherboard doesn't care either way how hard its screwed into your case (and trust me, i screw my things nicely) so it really isnt an issue. 

 

Rule of thumb. "Screw it tight enough that it wont vibrate, but you dont strip the threads"

[mariushm]

I could talk for over 10 minutes about this .. short answer is because a motherboard is not a gun and doesn't behave like a gun

 

Motherboards are designed and meant to be screwed into a chassis with multiple screws, to prevent board from flexing / bending when add-on cards are inserted, or to prevent the heavier cpu cooler from bending the board with its own weight.

 

mechanical stresses:

 

You are supposed to mount the mb into a chassis and have the back plate tightly press against the connectors, so that it would form a proper shield against EMI generated by the electronics on the motherboard (radio waves, switching noises from inside case power supply and so on). For this reason that back plate has some metal clips that behave like tiny springs which push against the motherboard - in order to screw the motherboard into the proper locations you often have to gently push the motherboard against the back plate so that screws would fit where they're supposed to.

Now imagine you put the motherboard slightly askew , just a tiny bit at an angle, and you put a screw in and screw it to the maximum and then you move on to put other screws in - you go to the opposite end of the board and you try to place the screw and you manage it but have to really work hard at twisting it in because the screw rubs against the metal of the hole.

What you're basically doing is you're now putting lateral pressure from two sides, like squeezing the motherboard.. you can end up with the board being slightly bent , like a convex shape. Afterwards, when you're trying to insert some thick connectors like the 24 pin connectors, you're only making it worse, because you're pushing the board down while it's ever so slightly bent upwards, so you can cause tiny cracks between layers of the motherboard.

Most proper tutorials about installing motherboards tell you to go and insert a screw partially, then go on the diagonally opposite side of the motherboard, place a screw there and twist it just a bit, and repeat the process with all the screws. As you do this, the motherboard centers itself naturally and it's not flexed or under mechanical stress in any way.

When all screws are inserted partially, you can of course go and tighten them some more.

 

Warping/flexing is bad, especially for bga chips like the chipsets for example these days... in the past it was quite often to see especially nVidia chips with bga balls having cracked solder joints under the chip (but admittedly nVidia screwed up some solder inside the chips themselves that made them more susceptible to failure)

 

temperature issues..

 

less relevant these days... motherboards are made of multiple layers , at least 4 and often up to 10-12 layers. Some layers (power and ground layers) have a lot of copper in them (which acts as a heatsink) and some layers are made only of thin traces connecting pieces together. 

Some parts of the motherboard can get very hot while others are cold (for example you may have 100c under the cpu vrm), maybe 50-60c under the socket, but only 30c under the pci-e slots.

It's a high temperature difference, and there's of course some temperature difference even between layers of the boards - those thick copper planes could be 5-10c colder than the signal layers.

Temperature can make copper expand laterally, and it's not uncommon for some copper areas to stretch by let's say 0.5mm , and these stretches can stress the vias and glues that bind multiple layers of the motherboard.. so some layers can stretch more than others. Tightening those screws to keep the motherboard very tight on the chassis won't help.

Of course, these days engineers have calculators and tools that calculate these things when designing the motherboards and try to reduce such expansions as much as possible and they're also careful not to place those screw holes between two hotspot areas (like for example in the center of a VRM), if you look at motherboards you'll see all hot areas are always between screws, very rarely crossing the invisible line formed by screws

 

and not last.. keep in mind that inside a computer there's a few moving parts like fans with their motors, hard drives with their motors .. and these things vibrate. Unless you add locking/ anti-vibration washers or train people to add loctite threadlocker (as user un-friendly as that would be) to the screws, the screws will eventually weaken anyway. So no sense insisting on some torque as eventually you won't have that

[Yoinkerman]

The forces that act on a pc while it's sitting on the floor aren't enough for specificity to matter.

[Jito463]

I agree with the others about the lack of necessity to "properly torque" the screws.  Having said that, I do use a torque cordless screwdriver/drill for convenience.  It has a setting from 1-10 + no torque.  I typically just leave it at 1, and that's sufficient to ensure I don't strip any screws while tightening them down.  Occasionally I have to carefully screw something in (easing off on the trigger button), even on the lowest torque level - and on other occasions, I have to raise the torque level up a couple notches (typically for case fan screws) - but overall, it works pretty well.

[Brennan Price]

Its just not worth the time to use a more complex tool over a simple screwdriver that gets the job done absolutely fine in the first place. Plus the fact that a PC is extremely unlikely to suddenly start throwing itself around the room in order to loosen the screws from which it is bound, therefore causing... Still no damage.

[Lord Nicoll]

4 hours ago, SportingKC said:

I have a background in gunsmithing and the cardinal rule for us is nothing gets screwed in or tightened without using a torque screw driver and precise pound per inch to ensure optimal (consistent) performance. 

 

Why don't PC builders follow similar canons? PCs experience various temperatures, are occasionally moved around, and contain dozens of fragile parts. To me, these are all reasons why properly mounting and torquing your motherboard, heat sink, and other components to a precise pound per inch is critical. But all I ever see is advice to "tighten things fairly tight, but not too tight," which drives me crazy because it's like someone defining a word with a word. 

because Intel specifies between 60 to 750 newton metres of torque for the CPU mount including the retention arm, often the mounds are plastic, it doesn't need to be cranked down, you'd probably crush the PCB and damage it too. The range of torque for a CPU socket is massive and Intels own stock cooler barely has any mounting pressure. A gun chamber as you know has to able to often hold up to 60,000 PSI, that isn't needed for a CPU. 

Words are defined with other words, that's how a written definition works. 

[Eaglerino]

We aren't putting together firearms that'll explode if assembled incorrectly or car wheels that will fly off if the lug nuts aren't on enough. It's a heatsink that'll sit in the same spot and position for extended periods of time with hopefully little movement, designed for the average consumer to get something wrong and still survive.

 

In other words don't over complicate things, it's fine

[NumLock21]

Too tight and it will physically damage the inner traces/layers of the pcb. Not too tight is so, the screws don't come loose. 

[Zodiark1593]

13 hours ago, SportingKC said:

I have a background in gunsmithing and the cardinal rule for us is nothing gets screwed in or tightened without using a torque screw driver and precise pound per inch to ensure optimal (consistent) performance. 

 

Why don't PC builders follow similar canons? PCs experience various temperatures, are occasionally moved around, and contain dozens of fragile parts. To me, these are all reasons why properly mounting and torquing your motherboard, heat sink, and other components to a precise pound per inch is critical. But all I ever see is advice to "tighten things fairly tight, but not too tight," which drives me crazy because it's like someone defining a word with a word. 

Compared to the temperatures used to heat metal, the temperatures expected to be absorbed within a PCB and heatsink is likely well below that required to produce any significant degree of flex and warping. The reason is that heat is generated in very small, localized spots. Though hot, the overall heat output in watts is quite minimal. Properly functioning, it takes a fair amount of energy to bring a heat sink up to 100C, and even then, your PC will probably fail before this occurs. Additionally, a PCB board will not absorb heat quickly enough to cause significant warping before failure of the component that is emitting the heat. If anything, the metal traces nearby the heat source will absorb the heat, and scorch the adjacent PCB before warping becomes a concern.

 

Also, with the exception of hard drives (which are probably torqued internally) and fans, there are almost no moving or rubbing parts that demand precision clearance. In an engine, parts tend to move and vibrate all the time, in a PC, not so much.

 

I'm not an engineer, but it stands to reason that low overall heat combined with static components do not require precise torque specifications.

 

*this applies to desktops. Builders may do different with laptops and other mobile devices that are subject to constant movement, though aside from shock during a drop, I doubt this is any more of an issue here either*

[Vegetable]

If you want to know the truth I lightly strip (or dont but just by a hair) every screw in my PC because I just tighten the crap out of them. It keeps whatever it is in place and ive never killed anything yet so come at me tbh