Would drilling holes in bootom of case 4 fans help @ all

[jadison]

I was curious if I had my case raised, and had 2 holes cut to allow 2 case fans on the bottom of my case, would this work.
What kind of fans would I need, and how big would the holes have to be?

jadison

[krusty the klown]

There's no reason why not (not that I can think of right now...) as long as there's plenty of clearance beneath your case and inside the case (above the fans - like near cards, etc.) to allow good air flow. Praps about one inch as a minimum???????

I guess you could pick up some 12V fans that are about the size of those in your power supply. This way, if you got an old CPU fan (they run on 12V) that has one of those in-line plugs that use an HDD power lead, you don't have to start butchering the wiring loom in the PC and the system can be easily removed. The best size for the hole(s) is to cut them the same diameter as the fan blades 2 get the best air flow. You might want to consider putting a grille or some wire mesh on the outside of the fans to stop them sucking in bits of paper and stuff into your PC.

....just my thoughts, anyway!...

[jadison]

seems like a good idea 2 me, (btw, the fans r blowing inward towards the PC, right, just don't want 2 mix that up).

Every bit of cooling counts!

[krusty the klown]

Aye, fans blowing cool air in at the bottom of the case - that way, you are helping the natural convection in the system (hot air rising, and all that!)

Just something to check: make sure your power supply fan is pumping air out of the system. I know this sounds really stupid, but there are some power supplies that pump air into the case. How dumb is that???

They are easy to take out and turn round tho!

[jadison]

What should I use as a stand to put my tower case on, so that the fans on the bottom have enough air and space.

Also what tool do I use to cut these holes w/ for the fan.

[Spencer]

If it's not enclosed in a desk(like mine, dumb idea), use a plastic monitor stand and drill coresponding holes in it as well. That will get you up about 3-4".

[wyvrn]

You can use wire snips or a jig saw. Use a drill for 4 starter holes at each corner and to drill the holes for the screw mounts.

[wtp]

yes it would help because it would force the hot air out of the case, cooling the case, and allowing the CPU to work better. It depends how big fan you get.

[jadison]

I was planning on using 2 secondary case fans to put on bottom of case blowing inward.

Now, so I drill 4 holes into the case bottom for each fan; each one being a corner, then, cut out a box shape from the 4 holes, stick the fans (1/2 way in, all the way in, or partly??) into the case, so that it's blowing inside. Do I use some sort of epoxy to hold the fans in there? I'll have 2 fans side-by-side u know?

jadison

[krusty the klown]

Most fans seem to have a square overall profile with little holes in each corner to bolt on to whatever they're attached to. There usually is a circular hole the same diameter as the fan blades themselves. If you (carefully) take the power supply out of your PC and open it up, I think you'll see what I mean.

Then just copy the method used by the power supply manufacturers for your case fan installation.

Krusty.

[This message has been edited by krusty the klown (edited 03-16-2000).]

[wyvrn]

Yeah 8 holes total I guess. 4 starter ones for the square you are going to cut, and four farther out to hold the fan in place. Epoxy would work, but it is more a permanent thing.

[German]

Jadison: sounds like you are on the right track here. In fact, some cases are designed to accomplish just the thing you're attempting to do. I have an Aopen full-tower which has four feet that swing out beyond the case - and elevates the tower about 4 inches above the floor. in the front of the case there is an - intake fan at the bottom - which draws air in through a duct under the front of the tower.

In the back of the tower there are two exhaust fan just above the power supply. And of course the power supply has its own exhaust fan. All totaled there are four fans controlling air into and out of the case.

Pretty cool http://www.sysopt.com/forum/smile.gif Let me know how your project turns out... cheers///German///

[Andy_L]

You would get more benefit from putting one in the bottom and on on the top (blowhole) we just did this on a friend o/c celeron and dropped temps 15 degrees on M/B and processor both. We used paint to draw a series of concentric circles, printed it out, taped the paper to the case and started drilling, we ended up using 8mm holes, but start small, it makes the drilling easier and you can judge what looks best before the holes get too big.

[jadison]

Well, I took off the plastic frame in the front, and took out that old PC speaker (which no one needs n*y*way), and replaced it with the 1st 3" X 3" Evercool fan:
http://www.angelfire.com/electronic/ntechcomp/case1.jpg

Now should I get another 3" X 3" fan and do what German mentioned...put one fan on bottom and one on top? (BTW, the bottom one blows inward while the top one blows outward.)

[This message has been edited by jadison (edited 03-16-2000).]

[This message has been edited by jadison (edited 03-16-2000).]

[This message has been edited by jadison (edited 03-17-2000).]

[Ed_S]

One thought regarding a bottom mounted fan blowing up into the case.
What do you plan to do about dust & dirt? Filter it?
Especially critical if this is a floor standing box. After all, the floor is where all dirt settles, and you'll be sucking up everything that hits in between room cleanings!

[jadison]

I'll have sort of a grill/filter mounted just below the fan that should capture 90% of the **** that might otherwise flow into the puter.

As soon as I get my site covered I'll post a picture of the setup, u'll see how not much dust/dirt will be sucked up due to the fact that the computer is on a homemade stand.

As for the one on top, I'll have to put a grill or filter, time 2 go 2 the local hardware shop....

[skywalker[TSG]]

sounds like a good idea
but remember to have some filters there
or ur case will be coverd in dust

[jadison]

Could someone show me what kind of grill would work well for this opening-->a pic would be nice...thanks

[krusty the klown]

Have a look at the back of your power supply.
(well both my work comp and home comp have got nice little grille things over them, anyway)

You can get similar grilles at RS components:
http://www.rswww.com/

but RS aren't the cheapest. You might be able to butcher some old electrical equipment for some of the required stuff.

[Gutter Ball]

You can also "punch out" those extra slots in the back of your tower for extra air flow. I have about 8 extra slots(for different mobo's I'm guessing) all punched out and air does flow out of them. I have two fans on the bottom blowing air in(one at the front of the tower, the other just off to the side, sucking air in from the side slots and angled so it blows up airwards), one of those HUGE exhaust systems under my AGP(really works, keeps my AGP cool to touch), a set of those 5.25 slot dual fan systems, my power supply exhaust and of course my Alpha fan! Whew, anyway, hope this helps somewhat.

[jadison]

I have those slots punched out...I'm gettin ready to go 2 the hardware shop and look for some sort of saw 2 cut through this metal case: 1-2mm thick!! I'll post pictures on my website if anyone wants to see them...website is in my profile, go to overclocking. I should have 'em posted by next week.

Thanks to all of you for helping out, as usual I learned alot. I wish I came upon this forum way sooner. In fact this was the 1st forum I had ever joined, and I've been using the net for about 5 years!

[Ed_S]

For a grill, just get an add-on automotive speaker cover. Would look good on visible surface, and some are thick enough to put a foam filter in. Also, put o-rings on the screws, under the fan and the grill, to absorb vibration & cut down noise.

[Ed_S]

OK, now that I see your pic of the case I realize that you meant lower front rather than actually raising it & putting fans horizontally in the bottom!

Wish I'd have thought of this earlier. Grills, fans, and (most important) INFO are available here. (http://www.2cooltek.com/)
Lot of good info on case mods there too!

Ed

[jadison]

I just went 2 the hardware shop and bought this Stanley 4-way Key Hole Saw, which came with 2 saws:
http://www.angelfire.com/electronic/ntechcomp/stanleytool.jpg

The employee working @ the hardware shop said this would cut through a computer case (mine being 1-2mm thick), after he drilled four 1/8" sized holes (1 for each corner), and saw from corner to corner (3" X 3" squares). Is this possible with my case, and that tool?


[This message has been edited by jadison (edited 03-17-2000).]

[Ed_S]

OK, got it. That's not illogical, but seems like overkill. The one in front should suffice. The blowhole on the top is a proven working method. Another way I've seen is to run a duct to the CPU fan from outside the case. See this (http://www.lostcircuits.com/advice/cooling/) article.

Got some new info, which also relates to another question you had. Remember I recommended Maximum PC mag? Just got the April issue & it has an excellent article on cases, cooling, & airflow. Really good issue this time! Several good articles, well worth getting even though it's expensive at the stores!

[disciple]

this guy has all the stuff you need and is very easy to do business with just click on the store icon when you get there. www.2cooltek.com (http://www.2cooltek.com)

[jadison]

No I meant what I said Ed_S...
One on top...one on bottom:

http://www.angelfire.com/electronic/ntechcomp/picturefanz1.jpg

http://www.angelfire.com/electronic/ntechcomp/picturefanz2.jpg

For a total of 4 fanz, 2 blowing air in, 2 blowing air out(exhaust). And since I'll be OC'ing my K6-2 500 to 600+ I'll need all the cooling I can get.

I'll have a stand to raise the computer 4" off the ground...and grills to put on the fans to prevent too much **** from getting in the puter case.

Does putting a fan on the bottom and one on top seem illogical?

All comments welcome

-jd-

[jadison]

I custom made a grill and placed it on the outside, while placing a 3" X 2" piece of filter material on the inside cover of the case covering the hole in front of the fan:
http://www.angelfire.com/electronic/ntechcomp/fanzgrill1.jpg

Time to make the one on top!

-jd-

[jadison]

Here's a concept I have, tell me if uv tried it, and/or if it works: http://www.angelfire.com/electronic/ntechcomp/caseconcept1.jpg

I would build a small case around the Power Supply to prevent harm to the insides.

I'm going to try it next week so reply soon.
Thanks

-jd-

[Ed_S]

Very nicely done drawing, jadison! http://www.sysopt.com/forum/wink.gif

I watch for case mods & I haven't seen anybody do that before!
Can't see that it would do any harm, but likewise see little advantage. Power supply has never seemed to be a major heat source. But I'll be interested in seeing the results!
Be sure it's properly grounded to the main case, and have extensions or Y cables on hand, as I doubt the stock ones will reach.

Oh, by the way, here's the reason I'm interested in case mods: My Custom Case (http://www.geocities.com/SiliconValley/Software/5467/case1l.jpg)
Would post as an image, but the pic's too big!
Couldn't get what I wanted so built it from scratch. Double-width, 17 bay (6 int), dual PS. Hidden air ducts built into panels. Done in top grade red oak, pictured prior to stain & finish.

Ed



[This message has been edited by Ed_S (edited 03-24-2000).]

[German]

Jadison: looking good! I have not been back to this site in a while, so I am just getting caught-up on your cooling project. To be sure, you should have ample cooling at this point. Someone mentioned a possible problem with dust being sucked in from the floor by the bottom intake fans. Surprizingly, I experience much less dust intake on my homebrew system with the bottom intake fan as compared to my Quantex system with no intake fan (something I am going to retify shortly).

I believe the reason is my CFM (in) is roughly equal to my CFM (out). With this arrangement there is much less of a tendency for the fans to create a vaccuming effect, and the only dust getting into the case is a result of dust being suspended in the air - and not from being sucked up from the floor.. if you follow me.

Right at this moment, I have my toes http://www.sysopt.com/forum/smile.gif under the front of my case (remember I have "feet" on my case which elevates it a couple of inches off the floor) and I can feel a "slight" draft of air being pulled into the case.

Bottom line is, you case temperature should be the temperature of the ambient air in the room. If the case temp is warmer than the ambient room temp as a result of component heating two things can help - A LARGER case, and/or pumping more air through the case.

Smaller cases are more difficult to keep cool as the amount/volume of air within the case is smaller, and therefore more pronge to temperature changes resulting from component heating. A larger case, with its larger volume of air, acts as a temperature resivour (sp?) http://www.sysopt.com/forum/smile.gif and is less subject to temperature change (heating). Small lake freeze easily, oceans not so easily - same logic.


Pop a temperature probe on the exhaust of your case and let us know what you are reading. Note any difference (the delta) in the temperature of the exhaust from the case, and the air temperature of the room where the case is located. This should give you a pretty good idea of the effectiveness of your case cooling system.

Ultimately the idea is to have adequate case cooling without overkill - and unnecessary FAN NOISE!!! //German//

[neo_otyugh]

good idea to put the power supply outside the case. with the case on and power supply inside the case i run very hot, over 45C for regular operation. that is with one intake fane and the power supply fan as exhaust. with an open case i run about 36-38C, and then when i take the power supply out and place it on top of the case i run at 32-34C.
the cover for the case also makes a great beverage stand...