My experiences with dust filters so far:
I've got two fans in the front with dust filters attached. I find those filters as one of the best and most simplest inventions ever.
Thx to Lian Li my fans are attached with rubber cuffs to the case which makes them almost completely quiet. No need to regulate speed.
I live inmidst the city and there's quite a bit of dust here. 2 months ago, I cleaned the inside of my PC for the first time in 2 years of use. It was amazingly clean for that period of time and I was very surprised. Sure, there was a millimeter of dust everywhere but I was used to much much worse.
I usually clean the filters once a week. The first sign is always the temperature. Get to know your new system. What temperatures and voltages are normal for it. Same goes for fan speeds. It takes a bit of time but it's important to know those things in case of an error.
I've just read your last post. I wouldn't recommend to run a system without dust filters nowadays. I would never go back to an open case as I had before. Or even just a case without those filters. They're amazing. You'll love them!
And it's not everything about the temps of course. Fans of graphics cards are usually the first things which will break. All fans will live way longer because of the filters. That alone is worth two 99 cent articles imo.
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From a physical POV a positive air pressure should be better. Why? Because it's always better that more air streams into a case as this allows for quicker air exchange ofc. If there isn't enough air streaming into it, the cooling may become insufficient quickly. Not really important for a desktop PC with onboard graphics but in quick change between CPU and GPU it may heat up pretty quickly and end up badly.
Negative air flow pressure could mean less dirt/dust when I interpret your argument correctly. But that's pretty much insignificant tbh. As it's totally normal that dust and dirt enters the case. But those filters make a
huge difference. And with huge I mean humongous.
Get two fans in the front or a big one and one in the back. Get the air filters in the front and you should be fine. Clean them at least once a week. You might have to clean them more often because of the dog hair and your smoking habit.
I can't tell what's worse here. Through smoking the dust filters get gluey and dust tends to stick even more and faster to them. Might be a killer combo with that dog hair, too. I'd rather have that mess outside of my case tbh. Especially when it's about new hardware which isn't necessarily that robust like the stuff from a decade ago.
Always check the temperatures. I'd suggest to use the program
core temp. It has an option to protect the system from overheating. If you're using AMD set it up for 59°C and you should be fine. You get a message when the cores should reach this critical temp (60°C is max for AMD) and it'll shut the system down automatically if you've set it up this way.
Try to get some rubber cuffs for the fans so the vibrations won't carry over that much to the case. (recommended for HDDs, too)
I wouldn't let the case open. It's a possibility ofc. I did this with my old PC. But beware that this is always an hazard source. You might spill a beer or a dog might freak out, little kids might come over and stick their fingers in it/whatever.
