Negative or positive pressure? Does it matter?

[The red spirit]

How the FF are you now trying to make out you know furmark was limited but before were standing by it as a stress test and driver or weva it sees furmark and limits output as I said.

But it's not driver, it's vBIOs that is limiting card speed. And if you want technical term, than it's firmware that does that, regardless of driver.

And no the bios sets initial limits, that CAN be defeated via power play tables on AMD on Nvidia they can't be defeated but the DRIVER can limit performance, as for which limits furmark I wouldn't suggest I Know it's the driver, but I sure as shit ain't taking your opinion for anything more than a opinion.

Well you can override vBIOS values, if you raise power limit in Afterburner, but I'm talking about stock cards and even then by max 50%.

 

[Ahhzz]

Guys. Original topic. Find it and stay there. Stop the back and forth, and debate the question on hand, please. There's some brilliant people in this thread, and on the forums, and they can all provide some quality input, but it's getting covered up by all this noise. Back to topic please.

 

[AusWolf]

Yawn
The primal95 and furryskidmark argument. Happy, happy, joy, joy!
There is no set in stone ocing guide everyone is obligated to follow. If your rig, does what you want it to do, the way you want it to do it, when you want it to do it. Rock on! Life is gud.
Just agree to disagree.

Let that be the last word on the matter.

Did you test your gpu thermals/noise with no front filter prior to the swap by chance?

No, I didn't. Even with no filters installed, I still want something to filter incoming air. That's why I put the radiator there, which was obviously a bad idea. Not only are my case fans too noisy when mounted horizontally, but also, the heat coming from the rad made my GPU a couple degrees warmer while providing no decrease to CPU temps whatsoever. There's a reason why I've always recommended people to mount AIO rads on the top (or back) of their case as exhaust, and I'll keep recommending it. This time, speaking from experience.

Another update: I've decided. Instead of continuing a never-ending debate, I'll test the theory myself. I took out my H100i, and started advertising it. It's a nice AIO, but I've had enough of Corsair's bazillion cable mess anyway. When it sells, I'll buy a 280 mm AIO and 2x 14 cm fans, and see what works and how. In the meantime, I've got my trusty be quiet! Shadow Rock LP installed with Intel stock power limits. Whey-ho, it's so nice to see 2.8 GHz all-core again! But who cares, I'm GPU limited 99% of the time anyway.

 

[Vayra86]

Yes. Look mate, I modded my own Polaris card vBIOS and no matter what software it runs, it has universal power limits. There's nothing Furmark specific that can hard your GPU. Perhaps old cards, which didn't have AMD PowerTune or nV equivalent, could indeed burn out or be damaged. But that's because they had piss poor cooling and just so so electrical components. And then you would need to go back to pre Radeon HD 6000 series for that. And then again why does Furmark get all shit? MSI Kombustor, OCCT stress test run literally the same thing and people are fine with that.


No, it's through vBIOS. Card OEM sets allowed wattages (yes wattages, there's small power limit, maximum power limit, TDC, TDP) for card.

I never said damage cards re read my post.

I said it doesnt work as a stress test or realistic scenario. That was the topic I posted about: relevance of the different tests you can run. And yes, similar tests suffer the same issues.

OCCT GPU is not OCCT CPU either, the latter is superb, the former only serves the purpose of testing power supply.

Either way; Furmark for thermals alone, which is where we departed it also isnt optimal.

 

[Shrek]

I think one thing that is left out by the negative/positive pressure argument is turbulence; turbulent air on a heatsink will help with heat extraction.

Guys, please, just one more time: I'm not concerned about dust! It goes wherever air moves. Period.

Both videos (in post 1) are basically a dust discussion, so I guess it was inevitable people would head in that direction; so I'd say dust was very much on-topic, and no, it doesn't go where the air goes; if one put in a switchback, the air would go round, but the dust would be caught.

 

[Mussels]

Jaysus, all the arguing
Let's simplify this issue and let it end

If a stress test exposes hardware flaws (furmark, open world beta) it's the hardwares fault.
If your system is stable in some tests but crashes or overheats in others... it's the hardwares fault (or your settings for it)

You can choose to run on the edge of stability knowing that you're fine for your average use case, but many people think thats daft, and want the system 100% stable and cool running no matter what's thrown at it, open world is a good example of how a new program can expose the same hardware flaws and things die.

Back on topic, airflow is good. the air must flow. negative and positive aren't the issue, it's making sure air FLOWS over what needs to be cooled, and out of the case. Dust buildup is a secondary concern after you have sufficient airflow for cooling.

 

[lexluthermiester]

airflow is good. the air must flow. negative and positive aren't the issue

This.

Dust buildup is a secondary concern after you have sufficient airflow for cooling.

Exactly. There has been no science based testing to show that Positive VS Negative air pressure collects more dust in one condition rather than the other. What testing has shown is that the barometric pressure in a PC in one condition VS the other is measured in the thousandths of a single percent of PSI. There is no tangible difference between the two in the context of a PC. Testing has also shown that what contributes most to dust collection in a case is environmental conditions. More dust in the environment, more dust in the case. Want to keep dust from building up quickly? Keep your environment clean. Vacuum frequently.

Where cooling is concerned, there is no measurable difference between positive & negative pressure. Cooling depends exclusively on air flow and proper heat conduction to the air. If you want to effectively cool your PC, configure your fans to extract heat from your system in a way that works with the laws of physics(thermal dynamics and whatnot). Hot air rises, cool air descends. Following basic science principles will help achieve an optimal cooling solution.

 

[Jetster]

There has been no science based testing to show that Positive VS Negative air pressure collects more dust in one condition rather than the other.

I'm not trying to beat you up but you keep saying this like its a fact. When it's actually an opinion. You given no scientific evidence to show that is does not

So here is a factual example that having more air being forced in with filters then is being sucked out the back will filter your air. So the majority of air will be as clean as the size of the filter. Yes he's a scientist.
If he adds exhaust fans to the top the presure in the case will drop and air will be pulled in from the back and everywhere else. Then that dust will increase but it will cool better. I rest my case, now I will go admire my dust free components.

 

[mtcn77]

I'm not trying to beat you up but you keep saying this like its a fact. When it's actually an opinion. You given no scientific evidence to show that is does not

It is not the consensus, it is a case of the more you know the less clear things become and vice versa.

 

[Jetster]

It is not the consensus, it is a case of the more you know the less clear things become and vice versa.

Consensus is the business of politics. Science, on the contrary - Michael Crichton

I'm not sure what you meant by that so I just went with some random quote. I'll stop now

 

[mtcn77]

Consensus is the business of politics. Science, on the contrary - Michael Crichton

I'm not sure what you meant by that so I just went with some random quote. I'll stop now

I think positive pressure is good, that is all. A lot can be said while refraining oneself from naming names which is what I did there.

 

[lexluthermiester]

I'm not trying to beat you up but you keep saying this like its a fact. When it's actually an opinion. You given no scientific evidence to show that is does not

Neither has anyone else. The diference is I'm University educated and have a great deal of experience in airflow design. However, I'm not willing to write a 4 page essay on the matter. The evidence is out there if you want to learn.

So here is a factual example that having more air being forced in with filters then is being sucked out the back will filter your air. So the majority of air will be as clean as the size of the filter. Yes he's a scientist.
If he adds exhaust fans to the top the presure in the case will drop and air will be pulled in from the back and everywhere else. Then that dust will increase but it will cool better. I rest my case, now I will go admire my dust free components.

Sorry, that video was all talk and no merit and did not help your position. They used a smoke machine in a VERY basic demonstration to show airflow through the front filter with & without front fans, nothing more. They did NOT show long-term dust build-up, nor comparative dust performance or thermal performance measurements in a positive VS negative pressure scenario. There was nothing in that video of any scientific value to this topic.

The misconceptions about positive & negative air pressure scenario's stem from the clean-room good practice models.

Cleanrooms | Negative Pressure vs. Positive Pressure

Learn the difference between negative pressure vs. positive pressure cleanrooms and discover how they can work for your application.

angstromtechnology.com

These kinds of clean room scenario's do not and can not apply to a PC case as the usage model is extremely different. The only way to prevent dust contamination in a PC case, or reduce it in any tangible manner, is to operate said PC inside a clean-room type environment. Dust contamination differences in common air environment electronics that need air-flow induced cooling is insignificant.

Dust is easily cleaned and is of minimal concern unless the user of a PC is either careless or lazy.

So the primary concern is, once again, cooling not dust. As there is no evidence to show that the differences between cooling effect between positive & negative air pressure in a PC case. The focus therefore needs to be on airflow. This is what the video effectively showed: Not that the filters were of any benefit, but that the addition of front mounted fans pulling air through that particular case created better airflow. It may not have been their intention, but is the result they proved. The filters actually inhibit airflow and as they collect large dust particles and become clogged, the airflow will dramatically diminish.

So once again, lose the air filters, add better fans and configure them for good airflow through your case, clean your system out every month or so(depending on how dusty your operating environment is) and enjoy!

 

[Deleted member 24505]

Well i am running mine positive. My temps are smashing, so i am very happy with it. 2x140 in on 280 rad, 2x120 in on 240 rad, 2x140 out No filters as i think the fact they filter dust is negated by the restriction and the clogging, which happens very quickly irrelevant of how clean you think your room is, there is always dust/skin flakes/smoke

 

[lexluthermiester]

Well i am running mine positive.

You say that, but with the open back like you have(shown here), the pressure differences are actually insignificant. What you have actually done is create an airflow scheme through that case which draws air in from the sides and expels it out the front and other holes in the case.

 

[Deleted member 24505]

You say that, but with the open back like you have(shown here), the pressure differences are actually insignificant. What you have actually done is create an airflow scheme through that case which draws air in from the sides and expels it out the front and other holes in the case.

I have covered the back as you can see on the pic Shall i cover the vents in the bottom panel too? apart from the vent under the PSU obvs

 

[DeathtoGnomes]

Dust is easily cleaned and is of minimal concern unless the user of a PC is either careless or lazy.

This. Nuff said on dust.

 

[Mussels]

Dust is easily cleaned and is of minimal concern unless the user of a PC is either careless or lazy.

Or has nerve damage in their elbow and back, and lives in a dusty environment

It's a terrible idea to assume motivations or reasoning for others

 

[mtcn77]

Or has nerve damage in their elbow and back, and lives in a dusty environment

It's a terrible idea to assume motivations or reasoning for others

He types utter nonsense unfortunately. Dust kills electronics. It is not how frequently it is removed that determines the build up. It is the filters and the compromise of clean vs dirty will be evident when the fin arrays of high heat components fill sooner and fans start failing, not before anything else.

 

[lexluthermiester]

I have covered the back as you can see on the pic Shall i cover the vents in the bottom panel too? apart from the vent under the PSU obvs

Are you going to tape up or cover every single crack and opening in your case?

Are you hell bent on maintaining positive pressure? You will not attain that goal without extreme measures and expense.

Or has nerve damage in their elbow and back, and lives in a dusty environment

It's a terrible idea to assume motivations or reasoning for others

While I meant no offense to you or anyone with physical limitations, taking the side off a case and blowing it out is almost a trivial task. There is also the option of having someone do it for you.

 

[Deleted member 24505]

Are you going to tape up or cover every single crack and opening in your case?
View attachment 217459
Are you hell bent on maintaining positive pressure? You will not attain that goal without extreme measures and expense.


While I meant no offense to you or anyone with physical limitations, taking the side off a case and blowing it out is almost a trivial task. There is also the option of having someone do it for you.

Well no, i'm sure every case made has multiple openings and cracks, so i won't be going full retard and sealing all of them. The rear fan hole did need taping though.

 

[ThrashZone]

Hi,
What you're describing is a test bench environment where there is neither positive or negative pressure issues.
Have fun dust be damned lol
https://modmymods.com/computer-cases/test-benches.html

 

[TheoneandonlyMrK]

Are you going to tape up or cover every single crack and opening in your case?
View attachment 217459
Are you hell bent on maintaining positive pressure? You will not attain that goal without extreme measures and expense.


While I meant no offense to you or anyone with physical limitations, taking the side off a case and blowing it out is almost a trivial task. There is also the option of having someone do it for you.

Not for all, the ease of removing and cleaning two 360 rads and 12 fans is non existent, filtering is the only choice since 6monthly clean outs are a pain, I'm doing it now it couldn't reasonably be done effectively monthly.
Each to they're own , cooling, noise and cleaning level s are a compromise and personal choice, with no set right or wrong, that's the problem with this debate.
We're all after slightly different end results on slightly different use cases.


As for all my deleted posts on here I'm starting to wonder why some get low quality posted where's mine are deleted, noice not.

 

[AusWolf]

Not for all, the ease of removing and cleaning two 360 rads and 12 fans is non existent, filtering is the only choice since 6monthly clean outs are a pain, I'm doing it now it couldn't reasonably be done effectively monthly.
Each to they're own , cooling, noise and cleaning level s are a compromise and personal choice, with no set right or wrong, that's the problem with this debate.
We're all after slightly different end results on slightly different use cases.

How about mounting fans on radiators in a "pull" config? It's much easier to blow dust off of the rad than removing the whole thing to have access to the side where the fans are.

 

[ThrashZone]

How about mounting fans on radiators in a "pull" config? It's much easier to blow dust off of the rad than removing the whole thing to have access to the side where the fans are.

Hi,
Sorry but you said on many occasions dust is not what the op is about
Have you changed your mind ?

 

[AusWolf]

Hi,
Sorry but you said on many occasions dust is not what the op is about
Have you changed your mind ?

I was replying to a comment about cleaning. My post that you quoted has nothing to do with my original question. Sorry if that caused confusion.

Also, just because I said that dust is not part of my dilemma regarding my choice of cooling, I still believe that one should clean their PC regularly.