Pirre

If you take a very loud 80mm Delta fan, the 80+ CFM one, and hook it up on to a Rheobus, would the noise level at let's say 7V be comparable to a low noise papst fan?

TeuS

I've got a quite loud delta (no 80 cfm tho), and @ 7v it isn't really silent but it isn't really too loud, my MSI Ti 4200 produces MUCH more noise (it's about time I do something to that sucker)

a 80 CFM delta will get quite silent @5v I think

mot:
Delta 80.2CFM, 52.2dBa

V7+ fan
Noise H 6000rpm@47 dB(A)
M 4800rpm@35 dB(A)
L 3000rpm@24 dB(A)

my V7+ @ 7v was quite bearable, but can't be called 'silent'
@5v it's quite 'silent' (silent is relative you know
-->for me it's really okay, but still too loud if you want a machine that's near silent

Pirre

i'm thinkin of buyin a rheo from 0-12V and use it for some case fans and a cpu fan, the delta 80+ CFM, so at low voltages I have low noise levels, but I got some extra room when I need extra cooling. But at 5V, what CFM rate could I expect?

TeuS

I'm also quite curious about that one :/
it's RPM related... but still can't make an estimation of CFM

hmm, I'll compare some papsts

80mm papst fans

model - rpm - cfm - CFM/RPM
NGL 1500 19,4 0,012933333
NGML 2050 26,5 0,012926829
NGM 2600 34,1 0,013115385
NM 2600 34,1 0,013115385
NG 3100 40,6 0,013096774
N 3100 40,6 0,013096774
NH 3600 46,5 0,012916667

so I think the CFM/RPM value is about constant

anyway, you need the RPM now so it isn't solved yet

Pirre

it seems that a fan that does 40 CFM at 6000rpm will do 20 cfm at 3000rpm, noise levels are proportional to this.
now i only need to know the rpm at 5V when it's 6000rpm at 12V,
proportional as well?

http://www.madshrimps.be/?action=get...=50&articID=37

I was thinkin of taking on of those heatsinks, the mcx4000 for a huge 80mm delta fan, with a rheo i could take noise levels down to whispersilent and still have good cooling, and have some 80CFM still there for when i need it, but looking at this
http://www.overclockers.com/articles373/ it seems that my current volcano7+ with fan is equally good or perhaps better ?

biCker

my delta ffb80-hp @ 7V makes a lot more noise then my papst ngml @ 12v

Pirre

but the delta will have significantly higher CFM at 7V than the papst at 12V ....


I'm looking for THE best P4 heatsink, to combine with a fan (coupled to a rheobus) that gives me low noise levels at 1.65-1.70V for a 500MHz OC and ofcourse acceptable temps.

biCker

atm, I'm running an antec blue led fan (papst ngml is a bit weak, delta a bit loud) combined with an Alpha heatsink, gives 50° stressed for a 450mhz oc

Pirre

if I would place this :

http://www.overclocking.be/?page=sho...03f01dc50c270e

on a Swiftech MCX4000 with a PAPST 120mm fan (55CFM at 26dBA)

and would have kick *** P4 aircooling with no noise ...?

my thermaltake volcano gives 49CFM MAX at 6000RPM and 47dBA!

or is it possible that you the 120mm fan won't be able to push the 55CFM through the fan adapter since you decrease flow area and hence build up counter pressure?

RichBa5tard

A 3000 rpm 80mm fan is the max you can go if you want to get it (pretty) quiet at 5V.

A papst NGH (or was it NG or NH?) at 3100rpm is the ideal overclocking fan in my humble opinion: not too loud at 12V and silent at 5V.

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