Panaflo 80mm L1A @ 12V Vs. 120mm low speed @ 5V??

gonsped · Post by **gonsped** » Fri Jun 06, 2003 2:15 pm

Which would be quieter?

Panaflo 80mm L1A (low speed) @ 12V OR

Panaflo 120mm low speed @ 5V?

For CPU cooling of course

dukla2000 · Post by **dukla2000** » Fri Jun 06, 2003 2:38 pm

My Papst 4412FGL @ 5V is far quieter than an 80mm 'flo L1A at 12V.

kogi · Post by **kogi** » Fri Jun 06, 2003 7:07 pm

a 120mm fan is a pain in the x to mount onto a heatsink. have U considered the Panaflo 80mm L1A @ 7v or 5v.

kogi

DryFire · Post by **DryFire** » Fri Jun 06, 2003 7:49 pm

not to mention a los of static pressure. meaning you need more cfm to do the same thing with lower cfm of an 80 mm fan.

now if your sucking air from a duct it's a different story.

so i'd say the 80 mm.

gonsped · Post by **gonsped** » Fri Jun 06, 2003 11:45 pm

The problem is that a Panaflo 80mm @ 5V just doesnt cut it at the moment.

I am cooling an XP1800+ CPU with a WBK 68 V1.0 hsink with an 80mm Panaflo connected to a 80-60mm fan adaptor running at 12V.

The PSU unit also has a 80mm Panaflo at 12V.

The Problem: idle temps with both fans at 12V is 48C for the CPU - with the computer case closed.

Reducing the PSU to 5V brings the whole inside of the case temp so high that the CPU goes way past 63+C - this is STILL idling.

Since the PSU makes the most noise - I need to lower it to 5V - but so far no go as not enough airflow inside the case.

I was thinking of using a 120mm fan connected to a fan adaptor on a SLK800U hsink running at 5V. But I am not sure whether the lack of airflow inside the case would help at keeping the temps on the CPU down at all. This way i can run both fans at 5V thus it should be dead silent - dun worry about the HDD for now......

My possible solution was to improve the airflow inside the case was to add 2 more Panaflo 80mm running at 5V - one at the case fan intake area and another on the underside vent of the PSU (like those dual fan enermax psus). 3 Panaflos running at 5V *SHOULD* give the same airflow as 1 Panaflo at 12V, no?

kogi · Post by **kogi** » Sat Jun 07, 2003 2:35 am

gonsped wrote: I am cooling an XP1800+ CPU with a WBK 68 V1.0 hsink with an 80mm Panaflo connected to a 80-60mm fan adaptor running at 12V.

An slk-800 and a fan running at 7v SHOULD cool your CPU adaqutely

gonsped wrote: My possible solution was to improve the airflow inside the case was to add 2 more Panaflo 80mm running at 5V - one at the case fan intake area and another on the underside vent of the PSU (like those dual fan enermax psus). 3 Panaflos running at 5V *SHOULD* give the same airflow as 1 Panaflo at 12V, no?

This seems like you are running 3 fans in series. This will NOT improve your airflow. You need to run the fans in PARALLEL to have any improvement in airflow. Does you case have any holes to mount an exhaust fan? What case are you currently using? Post us some pickies of your case!

kogi

dukla2000 · Post by **dukla2000** » Sat Jun 07, 2003 2:37 am

gonsped wrote:My possible solution was to improve the airflow inside the case

I would agree you will get a better bang for your buck by improving the case airflow. Right now you are dependant on the psu fan for case flow and as you noticed it needs to shift a lot of air (and be noisier) to keep things under control.

Also, while throwing more air at your CPU will help, I am sure less but colder air is more effective.

IMHO, the biggest bang/buck would be to add an extract fan below the psu (near the CPU) if your case allows it. 2nd biggest would be to add a 2nd fan to the bottom of the psu. Adding a slow (5V or 7V) 80mm front intake could be disappointing: it will not add much to the overall cfm already being sucked through your case by the psu fan. Another option that may be easier (depending on your case tinwork) would be to add a side fan blowing onto the vidcard and CPU - this has the same limitation as the front intake (in that it does not particularly increase case flow), but it does ensure cold air gets direct to where it is most needed.

JEN · Post by **JEN** » Sat Jun 07, 2003 2:52 am

You should be able to run the L1A on the slk800 @ 12v without adding any noise as its inside the case.

However, I thing 5v for the PSU is too low, I have them @ 7v and its cooling nicely as long as ambient temp is not over 26C

aphonos · Post by **aphonos** » Sat Jun 07, 2003 9:09 pm

dukla2000 wrote:Another option that may be easier (depending on your case tinwork) would be to add a side fan blowing onto the vidcard and CPU - this has the same limitation as the front intake (in that it does not particularly increase case flow), but it does ensure cold air gets direct to where it is most needed.

One caution for a side (or top) hole is that it provides a more direct route for sound to escape the case--whether noise from the fan on the hole or other internal component noises. *need a smilie with fingers in ears

* Good airflow from lower front to upper back of the case (ie ATX standard) is usually a quieter option. If you can get good airflow into the front, you can still direct cooling using a duct or actively cool components with undervolted fans. Usually the lower front openings are a bit blocked by the bezel which (does reduce some airflow, yes, but also) makes the sound take a turn before it launches out into the room.