Case Fan over CPU-Cool Idea?

[Posy Rorer]

I'm thinking of installing a std. 80mm case fan in front of my CPU/HS/Fan (blowing toward it) for additional cooling of the heat sink, and consequently, the CPU. (please see attached diagram).

Q. Will this interfere in any way with the original design of the Celeron 400 Slot 1 CPU/HSF arrangement? What about another case fan installed on the side of the case (near the PSU), hanging above the mobo/HS? Will the fact that it would be blowing air across the case interfere with the air flow that is supposed to be directed out the rear of the case (see diagram)?

Any benefit from drilling holes into the bottom of the case, or can they also interfere with the air current that is supposed to be directed out the rear of the case? (Anything I can do to improve cooling without having to buy expensive specialized cooling fans, I'm all for!)

Since my last computer (OC'd 486) was always filled with dust/dirt, I'm also planning on attaching panty hose over the fans and every opening on the computer, as a filter. Can this significantly affect my temps?

 

[Shroomer]

I use this idea on my rig BUT I have a socket A mobo where the fan (120mm, 7v) blows DIRECTLY into the heatsink. It gives me about 200 more rpms on the fan on my heatsink and brings the coolest air right to it.

I don't know how it would affect a slot mobo as they would be at a 90 degree angle. Perhaps one of those slot coolers mounted to the side of your case, but you would need an Alpha to suck the heat off to work.

I think you should either do it in anticipation of a socket mobo or come up with something else for your setup.

 

[Posy Rorer]

I use this idea on my rig BUT I have a socket A mobo where the fan (120mm, 7v) blows DIRECTLY into the heatsink. It gives me about 200 more rpms on the fan on my heatsink and brings the coolest air right to it.

I don't know how it would affect a slot mobo as they would be at a 90 degree angle. Perhaps one of those slot coolers mounted to the side of your case, but you would need an Alpha to suck the heat off to work.

I think you should either do it in anticipation of a socket mobo or come up with something else for your setup.

The proposed idea *does* have the 80mm case fan blowing directly on the heatsink (well, its toward the heatsink, but its about 5" away from it, and the RAM modules are in between). The original CPU fan would still be attached to the heat sink. Thing is, I'm not yet sure if this CPU fan is blowing into the HS or away from it, and if its blowing away from the HS (as appears to be), having another fan blowing air toward it might result in blowing hot air back toward the HS...

 

[craneage2001]

For my original setup, I had a generic heatsink with a 50mm Evercool fan (very noisy for its size, even rattled my case!) and a pair of 80mm case fans for throughput. I recently came across a 5in squirrel cage fan (6v) that connects to a 2"duct. It ran quietly so I cleaned it up (it was off of an old 1950's car for the heater). I cut a plate out of lexan and cut a hole making a tight fit for the duct of the fan. I cut a hole in the side of my case directly over my cpu and mounted the fan. I put a short 4" section of round duct to about 1" from the heat sink and removed the original hsf. I hooked up my new fan to a rheostat to adjust the speed. Before, my idle temps were just under 40 and under load I could reach the upper 40's, occasionally 50. Now, with only one case fan for exhaust, my idle temps are at 30C and load is at 37C. My motherboard runs at approx 2C above ambient. Now my computer is quiet and cool! This idea worked great for me. I don't see why it wouldn't work w/ a traditional rotary fan. I'll post some pic's when I get my camera fired up!