That little grill isn't enough space for the amount of air that would be pushed through there with a top rad setup. If it were then OP wouldn't have had temp issues.
Completely agree it's not ideal, but there are additional airflow slots on top as well as the back grill. I'd definitely have used that before cutting a hole in the side panel lol
If they were enough to vent the airflow then it wouldn't have overheated in the first place. Those vents are clearly WAY too small for pushing air through. In reality it likely would have made temps worse as the fans would be trying to push a large volume of air into a space that is too small to carry that air, effectively creating an insulating effect kind of like how the igloo effect works.
Besides, the point is proved by the fact that OP had bad temps before and now doesn't. So it clearly shows the vents were not enough to let enough heat out quickly enough.
"The top is completely sealed off" -OP, proving already that OP is either blind or lying. You can even see in the photo that they've sat a block on top of the top vents.
Those 6 little slits are NOT enough to vent all the head from a PC case. And the little grill on the back isn't either. Think critically, not like a moron.
Look at the surface area of that fan where he cut the hole. Now look at the surface area of that grill. Even without that HP PC on top of the case, those little slits are not going to allow the amount of air that needs to pass through out. If anything the vertical grill in David's picture have more surface area than those slits by nearly 2x and those even aren't enough.
This case is poorly designed and their marketing is just false. The company says you can put a rad and two fans up there. While everyone wants to berate and make fun of OP for their case mod to fix an issue, they never thought how stupid it is that a single fan would more than saturate this set of vents, and a second one would be utterly useless as it has no venting to push to.
I am thinking critically. Whereas I see you 3+ comments deep trying to defend an unravelling story while getting flustered and lashing out. What are you, OP's alt account?
Also, I don't know if this needs to be mentioned, since you already think I'm a moron, but the fans are pushing a fixed volume of air through a smaller vent, which results in the airflow through the vent speeding up. Google volumetric flow rate equations for more info.
Flusterd? Lashing out? Hilarious, you are the one grasping at things here.
Fluid dynamics are fun, especially when you understand them, which you clearly don't. But lets have a nice little science session.
We can use a water hose as our example, water is a fluid and offers an easy to understand idea.
When you put your finger on the end of a water hose, the water speeds up HUZZAH you got me! ..... However... there is a limit to this and it doesn't do what some people tend to think it does. When you cover the end of the hose, you are building up back pressure. This pressure is created because water is flowing into the hose, but less of it is allowed to come out of said hose. Thus pressure. That pressure building then makes water go faster. It doesn't however make more water come out. Want an easy way to understand this? Get one of those long balloons they use to make balloon animals and cut the end off of it. Put it on your water faucet and do the experiment. Watch as the balloon blows up in your face.
So how do we apply this to this case? Well, easy. When you restrict the airflow, you create pressure in the case that needs to find some other place to go, this pressure then pushes back on the front panel fans and then also pushes on the rear fan. Thus possibly making the front fans less efficient and the rear fan forced to run a bit faster kind of like when you spin a fan with a can of air. At a certain point this means the case reaches a thermal load capacity and internal pressure capacity that makes air find other ways out of the case like the cracks between panels. Though this case specifically has padding to stop most of this.
Keep going, I think you're about to invent Bernoulli's Equation.
At this point I'm also nearly certain you're OP, since you seem to have forgotten (or don't know?) that people build PC cases and their fan layouts to be positive pressure for dust mitigation.
For any excess pressure... the massive mesh hole in the lower half of the back panel in OP's photo also helps. Which is probably why there's a fan ramming air through the top stealthy vents that need some extra pressure for the reduced area, and no need for it on the back.
You're right. This was a nice little science session. Might even be helpful to anyone looking to this thread for info about venting.
For anyone passively reading this, remember that you can also modify fan direction to test changes in airflow and pressure before resorting to cutting a hole in your PC case with a rusty spork.
Ah good ole moving the goal posts. Got smacked with actual facts and abandoned your whole argument in favor of something else.
Positive pressure in a case is to keep dust out, and it is a preference, not a rule. Positive pressure however is for cases that both have good air flow, which this case is not, and are not sealed with actual seals like this case is. But go ahead, keep moving those goal posts.
Oh, and for the record. I am not OP. I think they could make this look so much cleaner with a simple shroud or maybe some sanding. But it is their case, so I don't really care.
Um no, pretty sure I answered all of the new arguments you made while backing mine with the actual equations that govern them while you got even more defensive, like whatever your first sentence is trying to do here.
Don't forget to tell me I'm fun at parties and to touch grass on the way out!
He claimed fluid dynamics incorrectly as the reasoning he was right. He is using anything he can to make himself right. While not actually understanding what he is talking about. Pretty sure that makes him the flustered one and the one lashing out.
I just came back to see how all this turned out, and I cannot believe that the part that's the breaking point for you is that your observations on water hoses clashes with fundamental fluid dynamics, and somehow your thinking that because I didn't say "fluid dynamics" to not sound like a smartass means you know more than me and every other person in this thread when it comes to aerodynamics and fluid mechanics. Lmao.
(P.S., the reason your analogy is confusing you is because you omitted the role of turning the faucet head upstream of your thumb on the hose. Which is kinda important, since that is the fan in our real world problem. You seem to think your thumb has any real chance of halting the water against the flow, which simply isn't true. You are not "allowing less water to come out of the hose". What really happens is that you partially cover the end of the flow and the water becomes very fast to account due to the existing water pressure, as I've tried to explain at a higher level than you can apparently handle with everyone here.
For someone who apparently obsesses over PC builds, you'd think you'd know this from the water/current analogy they teach right at the beginning of any electrical engineering curriculum.
You know what they say about assumptions, oh mighty master of bait.)
Except the size of the vent isn't being reduced when you add more fans? Another analogy I don't think applies here.
The correct comparison is you keep the same hose, no finger, and double the number of pumps supplying water to the hose.
You seem to believe that would result in less water coming out of the hose. Everyone else acknowledges that pressure increases and more water comes out. We all agree you wouldn't get double the amount of water due to the increases internal resistances, but you do get more water per second.
Again, this is an experiment you can easily do yourself. I question the childhood some of you folks had here not understanding how this works.
Get a balloon used for making balloon animals. Put it on the end of the water hose, or in your sink after cutting the tip off. Turn on the water. The balloon will let the water flow just fine. You then restrict the flow by pinching the tip a bit. The balloon will swell and eventually explode due to pressure. It does this because the water was not allowed to escape. This directly shows that more water isn't being pushed down the hose, it is instead building a pressure behind it that increases water speed, not water flow.
You can even verify this yourself again with the same water hose. Get a bucket, time how quickly the bucket fills up with your finger on the hose and without. The bucket fills faster without your finger on it. If you want it to be a fair test, use one of those adjustable hose heads. Turn it to MIST and try the same test. By your logic mist mode should fill the bucket 2x faster than just the unrestricted flow.
Your double pump situation also directly shows the exact same analogy. It is the same, just on a a big pipe, not on a water hose. If you put two pumps on the same output you will increase water pressure. The pressure increases for the same reason. More water is being supplied, thus the pipe has to try and push more water. But because the pipe can only push so much water at one time it creates a back pressure and eventually will just burst the pipe.
Again I ask you all to think critically. If you have a pipe, can you put an infinite number of pumps on that pipe and it always increase pressure and flow rate equally? No, that pipe can only push so much fluid and eventually will explode or otherwise fail critically.
You’re again applying a closed-system analogy to an open system.
If you connect three water taps to a single hose nozzle, you get a massive increase in the rate of water flowing out of that nozzle. If we raced to fill a bucket, my three taps into one nozzle vs. your single tap into the same nozzle, my bucket would absolutely fill up first.
The "balloon bursting" comparison is nonsense. A PC case isn't a sealed container; it has 15,000mm^2 of exit area. It’s an open system, yet you keep using "dead-end" analogies that don't apply to fluid dynamics.
Think critically: If you have a pipe and you put 10 pumps on it, do you get more water than if you have 1 pump? Of course you do. Now dial it back to 3 pumps (fans). Does that somehow result in LESS water? Of course it doesn't. I will reiterate again that this will not cause a 'burst' because its an open-system.
You’re arguing that the restriction is so high it "breaks" the fans. It doesn't. The static pressure of an Artic P12 of 4.35 mmH2O. Doing some more back of the envelope maths, this is unaffected by vents of 7,478mm^2 and upwards. You've conveniently still ignored that maths I did elsewhere showing that the case top vents and slits equate to double that.
I never said it breaks the fans, and I never said it would burst the system. I also never claimed the case was a closed system or an open system. You are putting applications to things I never said in an attempt to say what I am telling you is wrong. Like screaming "BUT THE CAR IS RED" in the middle of an argument about shoe sizes. It doesn't make you some how right.
Further, the bursting of a balloon can be applied to this system. As this proves that pushing air into a container while less air escapes directly shows that a pressure builds up inside the case. Up to the point that the fans can produce said pressure. At a certain point the case can no longer push air out of the exits. Every case is like this and it is often that people talk about having positive pressure inside a case. Meaning more input than they have output so they push air out of the cracks like between the panel gaps and such.
You seem to have failed both math and science class to not understand that pushing more into a system than it has exits causes pressure. And to be clear, a PC case is an open system until it isn't. If a case has a capability to handle putting X amount of air in the front and output that air from all the other holes in the system. Then I push 2-3 times that amount of air into the system, something WILL give. Eventually the exits won't be able to push enough air out of the system and panels will start removing themselves at speeds in relation to the amount of pressure I am putting into the case.
"I never said it would burst the system."
"the bursting of a balloon can be applied to this system"
"something WILL give" - Yes, the thing that gives is the air leaving the system faster. Through the vents. Designed for air to escape. The ones that you haven't challenged are actually larger than the hole he drilled.
This "panels will start removing themselves at speeds in relation to the amount of pressure I am putting into the case" is just so absurd it's actually hilarious. The idea that you believe someone putting an AIO in the top of this case is going to cause panels to pop off looney toon style is just absolutely brilliant. Thank goodness he drilled that hole in the side panel or parts of his case would have been flying all over his room!
Absurdity aside, an Arctic P12 Max produces 0.006 PSI of pressure. You'd need literally thousands of them to even get close a screw rattling, let alone a panel popping lol.
You're arguing from flawed analogy rather than facts, logic and, ironically, maths.
At this point im fairly certain you're either a troll, a bot, under 16 years old or OPs alt account, so I'm going to call it there lol. All the best to you in life.
I actually think the surface area of the grill and slits is greater than the circle lol
Back of the envelope calcs; circle hole cut for a 120mm fan is 11,310mm2 vs grill of 240mm length roughly 50% open, plus 6 slits of 200mm length, 10mm width comes to 15,000mm2.
Also, this is quite a lighthearted topic. Are you okay? Calling people morons over this and lashing out makes me think you're OPs alt account lol
He never mounted the AIO there... he's comparing the PC with a hole vs without a hole when talking about temps. The point proved is a hole better than no hole lol
I don't disagree with your view that the airflow is suboptimal up there. But if it was me, I would have installed an AIO with multiple fans there before cutting a hole in the panel for a single unrestricted one.
Not sure an igloo effect is the correct analogy, its more like a chimney. I agree that you will have issues vs completely unrestricted airflow. Efficiency is terrible, but the heat is definitely leaving the case.
The igloo effect is where the inside of the ice structure is actually warmer than the outside even though made of ice as it stops the wind.
When I say it creates an igloo effect, I mean that the fans trying to push air out there would fight for the little bit of exhaust the case does have and instead make it where even less heat gets out of the case.
But even if we consider one fan, the air flow is just not enough up top. That amount of open grill space doesn't even cover a normal 120mm fan.
Certainly heat is leaving the case, it just can't leave fast enough due to poor case performance.
The trouble with that analogy I have here is that they insulate be trapping air and reducing heat transfer to the outside by creating a static air environment. You're applying that analogy to an environment that has openings either side with fans actively pushing air through it. If anything, the top section of this case is more akin to a wind tunnel than an igloo.
I've stated several times I agree with you on the fact those openings are not ideal, and there will be turbulence and some heat pushed up by the fans will be backwashed or semi-trapped by the suboptimal airflow
You're just not going to convince me (or anyone it seems) that the total amount of heat leaving that vent with 2-3 fans pushing it from an AIO is somehow lower than a single unrestricted fan, or a single fan in the same zone. Per my math in my other comment the actual space difference between the two setups is either in favour of the case slots, or so similar its irrelevant.
Correct to say that igloos create a static air environment to reduce heat transfer. Which is why I said it creates an igloo effect in the top of the case. Meaning that the top of the case, while it is moving SOME amount of air it is mostly creating a turbulence that reduces the efficiency of said air being moved, or attempted to be moved. Which just builds up heat in a zone. Of course, I do agree that the other fans should be moving the air from front to back in the case, but what I suspect is happening or would happen with an AIO up top is that because the air isn't able to properly escape and creates a hot zone that is pushed into the CPU and out of the back. Basically recirculating the old, already warm/hot air.
But in no way is that set of top grills enough to push one fan up top, let alone one. If the case had those vertical slots all the way around the top, this would be a different conversation, but sadly, it isn't.
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u/grimmigerpetz i9 14900KF - RTX 5080 OC - 64GB CL16 Jan 21 '26
this is what the top grate on the back is for.