Custom Case plan with Questions

[lazyxeno]

Longtime listener, first time caller.

 

First, my background: I paid for food and incidentals in college by repairing computers and building systems for the more well to do students. But that was several decades ago, and Ive mostly been out of computer building, except for building a couple personal systems over the years. Current system being 7 years old now. So.. I'm not afraid of building, my I am well aware my experience is amateur and out of date.

 

Ive been wanting to build a new system for a while. As far as usage goes, I used to game, but these days its more spreadsheets and video. And if i do get back into games, its likely to be more in the WOW category than in the super heavy stuff. I want a decent system but I doubt I will need to live in the world of overclocking and fighting for a few FPS. I think I've got most of my parts planning needs met by reading other posts and watching LTT videos. and I already have a rtx2070 videocard and a thermal-take 750 watt PS. I'm inclined towards the X570 aorus MOBO and ryzen 5 3600 (using the included wraith cooler). I am not inclined towards making the jump to liquid or exotic cooling. One important detail: the area where this computer will live tends to be Dusty. Very Dusty. Dusty enough that I'm tired of having to open the computer to clean it multiple times per month.

 

In my current DIY mood, I want to actually build the case. I'm intending to use wood as my main medium, though a plexy window is under consideration. My carpentry skills are definitely up to the task either way, and I've sketched out a plan. On the dust front, I'm thinking towards air sealing the case except for fan holes, and then heavy filtering those. But heat exists. On the plus side, the ambient temp in the home area of this future computer is almost always 18C. I rarely have IO needs other than the basic, so I'm thinking all parts completely interior, with only one hole for all cords (power, two video, audio and a USB to externally placed hub) to exit, then permanently sealing that around the cords. For the fans, Ive got some filter material that I am confident will prevent any but the most minimal dust intrusion, but by the nature of filters, they will definitely make the fans job harder. The case will be side mounted to a wall, so the top and bottom will be unobstructed. I'm thinking 4 120 MM fans on the bottom inside, pulling cool air in through the filter, and 4 more inside on the top, pushing hot air out through more filters.

 

1) Is this a viable ventilation plan given current heat production of modern parts?

2) Should I be trying to keep the internal space as compact as possible, or is a larger internal cavity better

3) Is having the PS completely internal, with no separate external venting going to be a problem?

 

I'm sure that other questions will come up as I proceed, but these seem like basic important questions to seek counsel on before I start buying parts. I appreciate any advice this community can provide.

 

[Spakes]

5 minutes ago, lazyxeno said:

For the fans, Ive got some filter material that I am confident will prevent any but the most minimal dust intrusion, but by the nature of filters, they will definitely make the fans job harder. The case will be side mounted to a wall, so the top and bottom will be unobstructed. I'm thinking 4 120 MM fans on the bottom inside, pulling cool air in through the filter, and 4 more inside on the top, pushing hot air out through more filters.

Well, you can use fans thatfocus more on pressure than speed and CFM, can't recommend any since I'm not really into fans and stuff.

7 minutes ago, lazyxeno said:

1) Is this a viable ventilation plan given current heat production of modern parts?

 

Well, you can see how Fractal Design Meshify C is constructed, so the only problem with wood would be if something shortcurcuits, it might start a fire, so some coating will be needed. Also you'll need some exhaust holes, at least one on the back (that can be lightly filtered), plus one for PSU on the bottom. I would also suggest one or two fan holes (also filtered) on the bottom and one or two on the top of the case... Otherwise, airflow might be insufficient, IMO.

13 minutes ago, lazyxeno said:

2) Should I be trying to keep the internal space as compact as possible, or is a larger internal cavity better

To be fair, unless everything is crammed together tightly, going as compact as possible ain't that bad. Too small, though, won't be enough. Same with going too big, except it's not a good idea because there's no usefulness unless you have EATX board or two systems in one tower.

15 minutes ago, lazyxeno said:

3) Is having the PS completely internal, with no separate external venting going to be a problem?

If you mount it in top position, then it will be fine since it's gonna use insides of the case for cooling, but I would suggest mounting on the bottom with separate dust filter that is in between light filtering and hard af that you plan. Just my opinion, though.

[TVwazhere]

14 minutes ago, lazyxeno said:

1) Is this a viable ventilation plan given current heat production of modern parts?

2) Should I be trying to keep the internal space as compact as possible, or is a larger internal cavity better

3) Is having the PS completely internal, with no separate external venting going to be a problem?

1. I would say yes. a R5 3600 isnt particularlt hot even when OC'd, and the RTX 2070 GPU's are usually pretty beefy (3 slot) to help hrwally soak the heat. If you use static pressure optimized fans, you should be able to overcome most of the resistance caused by any heavy dust filter medium you choose, but this will ultimately depend on the filter, and how fast you want the fans to run.
2. I would say less space is better, as having more space doesn't necessarily mean better cooling, if anything, it allows heated air a better chance to recirculate throughout the case instead of linearly flowing through the case.
3. Yes, as long as you have a good intake and good exhaust, the rest of the case can be as air tight as you want. (you dont need filters on the exhaust side though.)

If you want some inspiration, there's a build log going on right now:

 

[lazyxeno]

4 minutes ago, Spakes said:

 

Well, you can see how Fractal Design Meshify C is constructed, so the only problem with wood would be if something shortcurcuits, it might start a fire, so some coating will be needed. Also you'll need some exhaust holes, at least one on the back (that can be lightly filtered), plus one for PSU on the bottom. I would also suggest one or two fan holes (also filtered) on the bottom and one or two on the top of the case... Otherwise, airflow might be insufficient, IMO.

 

Coating, yes. Painted wood, with offsets and rubber matting where appropriate. Actually my next question was going to be if there is any reason to use brass offsets as opposed to nylon. RE exhaust holes and fan holes.. Are you saying beyond the planned 4 fan inlet holes in the bottom and 4 fan outlet holes in the top?

 

 

[Stu_Bear]

A wood case would be awesome...would like one myself...maybe we can use your plans once you are done.  If you are rolling your own...you can go bat-sh!t crazy with fans...and not talking about the wimpy ones you see in PC cases.  

 

[Spakes]

3 minutes ago, lazyxeno said:

Actually my next question was going to be if there is any reason to use brass offsets as opposed to nylon.

Well, brass is harder than nylon, plus (IMO) it's easier to work with.

4 minutes ago, lazyxeno said:

RE exhaust holes and fan holes.. Are you saying beyond the planned 4 fan inlet holes in the bottom and 4 fan outlet holes in the top?

Wait, 4 for the bottom and 4 for the top? That will be way more than sufficient, to be fair... Though, I would do 3 on the bottom (PSU + intake), 2 on the front (intake), 2 on the top and 1 on the back (exhaust).

Though, you can do 2 on the bottom and 2 on the front as an intake and 3 on the top and 1 on the back as exhaust. Because if you do the kind of airflow that comes from bottom to the top, that might reduce cooling capability of CPU cooler. Not that it would matter too much, but just something to keep in mind if you decide that OCing the shit out of your hardware is what you're gonna do.

[lazyxeno]

2 hours ago, Spakes said:

Well, brass is harder than nylon, plus (IMO) it's easier to work with.

Wait, 4 for the bottom and 4 for the top? That will be way more than sufficient, to be fair... Though, I would do 3 on the bottom (PSU + intake), 2 on the front (intake), 2 on the top and 1 on the back (exhaust).

Though, you can do 2 on the bottom and 2 on the front as an intake and 3 on the top and 1 on the back as exhaust. Because if you do the kind of airflow that comes from bottom to the top, that might reduce cooling capability of CPU cooler. Not that it would matter too much, but just something to keep in mind if you decide that OCing the shit out of your hardware is what you're gonna do.

My original thought had been 2 in 2 out.. But then I bought the filter and started worrying about heat, since the fan holes will be the ONLY source of ventilation and doubled it. I also have a spare 180 MM fan I had considered using for the out in some fashion.

 

I would love a bit more of an explanation as to why cooling bottom to top would be less beneficial than sides? My general thinking was hot air rises, so push it all the way it wants to go, and just do top and bottom to create somewhat of a wind tunnel effect. If there's a reason to reverse, push hot out the bottom, that would be an easy switch, but going out sides would require a bit of redesign, so I want to make sure Im understanding. 

 

 

[Chiyawa]

32 minutes ago, lazyxeno said:

I would love a bit more of an explanation as to why cooling bottom to top would be less beneficial than sides?

All I can think of is that it is a bit hard to clean the bottom of the case and harder to access the fan, as you need to lift the case up to access the fan. Many cases do have removable filter, however.

 

Anyway, another factor is the air restriction. Because you only have a few mm of space between the bottom of your case and the floor or table, sucking the air can prove to be a challenge for your fans. Unless you have perforated surface or holes underneath your case that can provide good airflow, using bottom of the case as intake is not very efficient.

[lazyxeno]

3 hours ago, TVwazhere said:

1. Yes, as long as you have a good intake and good exhaust, the rest of the case can be as air tight as you want. (you dont need filters on the exhaust side though.)

Thanks. That build log is way fancier than the effect I am going for, but im definitely cribbing a few ideas even after just a cursory read through. Lol

 

The exhaust does need filters. Especially if its top exhausting, When the computer is off, and therefore fans off, dust will settle down onto it. Even if it weren't top exhaust, filtering EVERY possible point of dust ingress will benefit my desire to open this case as rarely as possible. When I say dusty, I mean that I will regularly be using a router and sanders within 5 feet of this box.

 

 

[lazyxeno]

Just now, Chiyawa said:

All I can think of is that it is a bit hard to clean the bottom of the case and harder to access the fan, as you need to lift the case up to access the fan. Many cases do have removable filter, however.

 

Anyway, another factor is the air restriction. Because you only have a few mm of space between the bottom of your case and the floor or table, sucking the air can prove to be a challenge for your fans. Unless you have perforated surface or holes underneath your case that can provide good airflow, using bottom of the case as intake is not very efficient.

I guess I mentally glossed over that detail: In this situation, it will be side mounted to either a desk or a wall, not sitting on a desk. It will have minimum 12 inches to the next thing below it, and possibly several feet, depending on what end up going with for final position.

[Chiyawa]

2 minutes ago, lazyxeno said:

I guess I mentally glossed over that detail: In this situation, it will be side mounted to either a desk or a wall, not sitting on a desk. It will have minimum 12 inches to the next thing below it, and possibly several feet, depending on what end up going with for final position.

Oh, okay, then. I don't see any reason for not making the bottom of the case as intakes. Sorry about that.

 

However, generally speaking, that's the reason why bottom intake is not well receive (at least for most people who put their desktop on the table or floor).

[Spakes]

4 hours ago, lazyxeno said:

I would love a bit more of an explanation as to why cooling bottom to top would be less beneficial than sides?

If you mount your CPU cooler like most of the people do, that will mean that fans will blow the hot air at the back. Plus if you do only bottom-to-top airflow, your CPU cooler might catch a bit warmer air than what's possible with side vents. Not that it would benefit much, but PBO on Ryzens does require as much cooling capability as possible for maximum perfomance (CPU will overclock itself, which will result in better perfomance, though not by a huge margin).