How to mod a Compucase 6A19

[Oldjim]

I got this case because of having 120mm fans front and back but I am having problems with the air flow - I think.
My cpu at 2300 MHz is cooled by a Zalman 7000A AlCu and under load gives these temperatures with the system temperature at about 32/33 deg C.
With case side removed 50 deg C
With case side on but intake filter and plastic grill removed 53 deg C
With case on and filter/grill in place 56 deg C
At present I have two SilenX 120 mm fans 14 dBA version one sucking in the front and one exhausting out the back.
PSU is Tagan 480 watt which basically doesn't push out much air.
Assuming adding an extra 120 mm fan in the side panel would help would it be better to have it pushing air into the case (I would then have two fans pushing air in and one extracting plus the psu fan). The reason for suggesting the extra fan should push the air into the case is that if it was extracting it would probably suck hot air from the psu right into the cpu cooler.
Is this the best way to go or do I need to consider a more radical solution.

[benighted]

I would make a blowhole in the top. Exhaust fans are the way to go IMO.

[Gizmo]

Try unplugging the silenx fan at back. If you can do it, ganging both fans at the front might achieve what you need without chopping up the case. I think your problem is in two parts:

1) Not enough cool air moving into the case

2) Hot air around PSU is not getting pulled out.

[Oldjim]

Gizmo,
That is exactly the problem.
As a test I unplugged the rear fan and the whole case got a lot hotter which tells me that the front fan just isn't pulling in enough air by itself.
Unfortunately the there is no room between the hard drive cage and the fan to put another in tandem.
I think that this leaves 2 options
Find another fan for the front with a much higher capacity or fit another intake fan in the side.
In theory and maybe practice adding a blowhole should help but only if the case is under positive pressure which at present I don't think it is when the intake fan is sucking through the filter.

[Gizmo]

I agree that putting a blowhole in the top is probably not going to help too much if you are already under negative pressure.

An intake in the side that pushes air toward the CPU might help your problem.

[Oldjim]

Update - changed front fan to YS-Tech 120mm fan (very powerful and noisy) with Vantec speed controller.
Running with input filter and front grill on at max fan speed CPU temperatures now 52 deg and at min speed (reasonably quiet) 54 deg under heavy load (Doom 3) and case temperatures lower also. This is not much different to the SilenX with the filter and front grill removed.
Reason I picked the YS fan was that the maximum current draw was much greater (twice) than the Enermax at not much different max flow. I assumed that the difference was that the YS had a higher pressure curve and this seems to have been correct as the min flow is probably not much different to my Silenx max but at much better pressure characteristic so pulled a lot more air through the filter.
Seems to have solved the problem as I can now run with my dust filter in place.