PSU Fan Mod

[redivulpis]

I'm planning an mITX build in the near future, basically planning to cram as much stuff into a Sugo SG05 as I can.
Since the SG05 only supports SFF PSU's out of the box, I've decided to follow in other modder's footsteps and use a full ATX power supply instead. The trick here is that I'm planning to use it as the main exhaust for the whole system, as well as the source of airflow for the i3-4330, cooled passively by a Samuel 17.
This is my first foray into passive cooling a CPU (I did use a passive sink on a GT 6800 about 10 years ago), so I'm not absolutely sure how much airflow I'm going to need.

The plan is to crack open the PSU I have now as a trial run, install a Noctua 140mm PWM fan, run it from the PSU power directly, and have a PWM control cable exit the PSU, then plugged into the CPU_Fan, header.

I also plan to sleeve all of the cables, to optimize cable length and airflow in the case. The intake will probably be a standard Gentle Typhoon. I prefer positive pressure whenever possible.

Thoughts?

 

[ymic]

If you are using it as the only source of airflow find a fan with a high static pressure rating. CFM ratings are for when there are no obstructions in the way. Corsair SP120's are good, unfortunately they don't make a 140mm version.

 

[redivulpis]

If you are using it as the only source of airflow find a fan with a high static pressure rating. CFM ratings are for when there are no obstructions in the way. Corsair SP120's are good, unfortunately they don't make a 140mm version.

Thanks, I'll definitely look into that.

Taking that into consideration, I'm thinking about fabbing an adapter plate to allow me to use a PWM modded GT AP-30 to be used in the PSU, since that'll be positioned directly above the heatsink.
of course I could just leave out the PSU fan, but I'm not crazy about that idea.

I wonder if I were to go with a positive pressure system, with the PWM AP-30 flipped to pull heat away from the processor, mounted to the Sam17, would a passively cooled PSU (purposely passive) act as a secondary heatsink?

EDIT: Perhaps something like this: Rosewill SilentNight

Keep in mind, I'll also have a Superclocked GTX760 in the case as well, probably the open-air model from EVGA.

 

[ymic]

Not sure what you mean by "act as a secondary heatsink". An i3 isn't going to generate tons of heat, the 760 will probably make the most heat of everything you listed. Is there something stopping you from running a fan on the Sam17 and in the PSU? or just trying to go for low noise?

 

[redivulpis]

Not sure what you mean by "act as a secondary heatsink". An i3 isn't going to generate tons of heat, the 760 will probably make the most heat of everything you listed. Is there something stopping you from running a fan on the Sam17 and in the PSU? or just trying to go for low noise?

Just going for low noise really. I feel like having fans in both places might cause more turbulence with the air flow. With the larger fan in the PSU pulling all of the air from the case, including that which flows through the CPU heatsink, it should be a bit quieter. Also, since the i3 won't be generating a whole lot of hear, I figure more fans might be overkill anyway.

 

[ymic]

Right, with the i3 I'm sure you be fine if you get a fan that has enough static pressure. If it's PWM it will also be quiet unless things get warm as well.

 

[redivulpis]

Got the motherboard, processor, RAM in today and put it all together with the stock Intel fan. Looking at the board and images of the Sam17, I'm not really sure I'll be able to orient everything to fit. it looks like the heatpipes might interfere with the GPU or the RAM depending on how I install it. Still kinda working it out in my head. I might pick one up still to test fit and use it in a different build or sell it here if it doesn't work out.
Backup plan is to just use an NH-L9i with a fan and still swap in a PWM for the PSU fan but run it off the Case_FAN header.

 

[larrymoencurly]

I'm thinking about fabbing an adapter plate to allow me to use a PWM modded GT AP-30 to be used in the PSU, since that'll be positioned directly above the heatsink.

Be very careful about trying that because one of those big heatsinks may have 340 volts DC riding on it, and you want to keep any adapter plate at least 3/8" (10mm) away from all the heatsinks, not just to avoid high voltage but also to prevent anything on the low voltage side of the PSU, like the big heatsink holding the output MOSFETs or diodes, to come into contact with anything on the high voltage side. I strongly suggest you make any adapter plate out of plastic, not metal.

The inside of a PSU is much more dangerous than anything else in a computer.

 

[redivulpis]

Be very careful about trying that because one of those big heatsinks may have 340 volts DC riding on it, and you want to keep any adapter plate at least 3/8" (10mm) away from all the heatsinks, not just to avoid high voltage but also to prevent anything on the low voltage side of the PSU, like the big heatsink holding the output MOSFETs or diodes, to come into contact with anything on the high voltage side. I strongly suggest you make any adapter plate out of plastic, not metal.

The inside of a PSU is much more dangerous than anything else in a computer.

Excellent Idea. If I end up using a 120mm fan in the PSU, I'll definitely be using plastic for any fabrication work. I'm looking more into 140mm options to avoid any extensive mods to the PSU. I absolutely understand the danger involved in poking around with capacitors and stuff. Not in a hurry to get tazed.