OT: 1U HELP Firewall - with build in Harrier Jump jet fan (suggestions for fan)

[NAS]

Normally i would not go this OT but I am at my wits end. I upgraded one my firewalls here and the new hardware has a CPU fan that is so unbelievably loud. I cant get the exact specs but it has to be pushing 40dB (its that bad).

 

I have got the thing in bits and its a side ways draw, blow down semi closed 60mm fan (with bespoke approx 68mm diagonal mounting screw holes so no direct replacement possible). I reckon i could easily fit a 80mm 3 pin fan between the heatsink and the case lid and if it was 15 mm deep that would leave a couple of mm free.

 

Not being a fan expert I am concerned that there wont be enough room to draw air from above but at this point I am at my wits end and NEED to replace this fan and damn the consequences.

 

Anyone got any suggestions so I can stop getting daily headaches

 

Help !

 

Note: P4 2.8Ghz and the 3 pin fan sounds like its speed controlled cause it changes pitch to be just that bot more annoying

[praeses]

Sleeved non-PWM fans generally offer the more pleasant noise signature at the cost of longevity and airflow-temperature scaling.

 

There are three 80x15mm fans that I know of in retail, unfortunately I don't know their models off the top of my head.  From quietest to loudest there is Evercool (sleeved), Zalman(BB), and Delta's (BB).  There are however a plethora of 70x15mm fans.  I found that the older 70x15mm (or maybe they're 70x10mm) OEM Opteron fans were comparable with anything on the market and have had great success with those.

[vca]

Normally i would not go this OT but I am at my wits end. I upgraded one my firewalls here and the new hardware has a CPU fan that is so unbelievably loud. I cant get the exact specs but it has to be pushing 40dB (its that bad).

 

I have got the thing in bits and its a side ways draw, blow down semi closed 60mm fan (with bespoke approx 68mm diagonal mounting screw holes so no direct replacement possible). I reckon i could easily fit a 80mm 3 pin fan between the heatsink and the case lid and if it was 15 mm deep that would leave a couple of mm free.

 

Not being a fan expert I am concerned that there wont be enough room to draw air from above but at this point I am at my wits end and NEED to replace this fan and damn the consequences.

 

A couple of points:

 

1. Since the days of about the early P4 chips processors have has some internal circuitry to monitor their temperature and in event of it getting too high, to throttle back their speed to reduce the power consumed.  This way if a fan dies or the heat sink comes loose the processor does not burn up.  So even if your replacement fan does not do a good enough job, you should be safe.

 

2. you used to be able to buy little screw on drive cooler fan units, these were quite thin as they attached to the controller board side of a hard drive and did not have much clearance between them and the drive below.  They worked reasonably well even though the air channels were quite narrow (on the order of 5mm).  The usual problem with these is that the fans would usually seize up after a year (or less).  So even with a small amount of clearance you will probably be ok.  The downside might be that the small clearance gap helps make things noisier.

 

3. you may be able to address the fan speed cycling issue though a BIOS setting, perhaps even just disabling the "intelligent fan control" option to leave the fan running full speed.

 

 

[NAS]

Thanks for the advice so far.

 

I am getting the feeling that i will be safe with an aftermarket 70-80mm fan with a couple of mm space above it will do some more reseach on what i can source.

[NAS]

The official word from the hardware firewall supplier is "tough there is no official replacement". Strange since the kit is design for SME and is completely unsuitable to any company without a dedicated equipment room.

 

Anyway my current plan is to remove the stock fan and case lid and fabricate one from Plexiglas adding a 120mm fan directly above the CPU drawing air in from the outside and forcing it onto the CPU heatsink. This is a bit more work and definitely uglier but should result in better cooling than stock and will be hidden by the rack cabinet.

 

Thanks again to all that posted advice. Appreciated.

[bubbaQ]

If you are are going to make a lid with a hole anyway, don't make a 120mm hole.... instead mount an 80 to 120 fan shroud adapter to the outside of the lid, and a small duct on the inside to force airflow directly to the CPU heatsink.

 

Or alternatively, depending on the clearance inside above the heatsink, mount the shroud to the CPU, and then use a 120mm hole in the lid.

 

But don't just put a 120mm fan in the lid above the little 80mm heatsink.

[NAS]

Not knowing the ins and outs of cooling I dont know why this is a better solution?

 

Surely a 120mm 60cfm fan <10mm above the heatsink to replace the 50mm closed fan is a superior solution without having to add ducting?

[bubbaQ]

Surely a 120mm 60cfm fan <10mm above the heatsink to replace the 50mm closed fan is a superior solution without having to add ducting?

 

Actually, yes it would.  A 120mm fan is MUCH larger than the crossection of the sink, so the vast majority of that airflow is wasted.

 

You don't necessarily need to duct the 10mm from the sink to the case lid, but you definitely need to duct the 120mm down to 80mm.