Semi-passive: anyone just disabling/replacing vid card fans?

[miller]

I have a (loud) XFX PCIE 6800 XTreme

http://www.newegg.com/product/product.a ... 6814150130

I know I can get kits to make it quieter/fanned or silent/fanless. But I was just thinking...

Why not just remove the HSF cover panel, disable the onboard fan, and position an 80mm Panaflo kind of up close at the heatsink surface.

Anyone here even tried anything like that? Or seen an implementation?

Have big case with good venting, and overall plenty cool, mostly quiet system. Just need to fix this video card part.

-- Asus A8N-E, Athlon 64 x2 3800, Scythe with fan on
-- replaced NB fan with fanless Zalman NB47J
-- Seasonic S12-430
-- Massive old antec aluminum case ??model

Soooo...anyone tried this?

[IsaacKuo]

Why not just remove the HSF cover panel, disable the onboard fan, and position an 80mm Panaflo kind of up close at the heatsink surface.

Anyone here even tried anything like that? Or seen an implementation?

I do this sort of thing all the time, but never with a particularly powerful video card. I'm not a gamer, so I've never used a really powerful video card.

I'm not up to speed on GPU tech, but based on the price I'm guessing this isn't a "high end" video card, but rather a mid-level card. (On the upper end of my personal experience.) My gut feeling is that a low speed 80mm fan aimed vaguely at it will do perfectly fine.

One thing--remove the onboard fan entirely, don't just unplug it. If you leave it in place, then it'll block a lot of air where you want it the most.

It should be easy to remove. Either it'll be screwed in, or it's held in place by some sort of plastic frame. The former is removeable in the obvious way; the latter will pop right off if you use needle-nose pliers.

[lemons]

I tried that with my last card. 6600gt. Removed the fan and lid thing that screws on to the heatsink and made a little bracket to fix a 120mm fan in the pci slot below the card.

Even with the 120mm fan on 12v blowing a gale the temps were very high. Didn't really understand why. I think that a small fan pushing air outwards through the small gaps in the heatsink must be much more efficient to simply blowing lots of air at the heatsink.

My card had the nvidia reference heatsink, pretty similar to the one on your card.

[Le_Gritche]

Even with the 120mm fan on 12v blowing a gale the temps were very high. Didn't really understand why. I think that a small fan pushing air outwards through the small gaps in the heatsink must be much more efficient to simply blowing lots of air at the heatsink.

I experienced the same thing (albeit with a half less power hungry GF4 MX440).
When the fan became noisy, first I removed it and suspended a 80 mmm fan between the end of the graphic card and the end of the sound card below. I opened the PCI bracket in between to allow the hot air to leave the case.
No problem at idle or under light gaming, but the result wasn't satisfactory when gaming with the overclocked GPU.
I put the fan back and soldered the fan red wire to a switch to allow for choosing between passive, 5V and 12V feed.
That small fan at 12V is as noisy as the 80mm fan was at the needed speed, but the result is cooler (or rather only hot to a point I'm not worried anymore)

You have a more powerful video card (50W or so under load I would say), I don't know what are the possibilities with undervolting and/or underclocking it, as well as controling the fan speed. You should start there I think.
I'm afraid the lost efficiency of barely blowing air toward the heatsink would make you run the fan faster, offseting any quietness you could have gained by using a bigger fan.

Anyway, the best way to know is probably to try it and monitor the temp of the GPU with the Nvidia utility if it's a supported feature.

[jaganath]

Even with the 120mm fan on 12v blowing a gale the temps were very high. Didn't really understand why. I think that a small fan pushing air outwards through the small gaps in the heatsink must be much more efficient to simply blowing lots of air at the heatsink.

IIRC axial fans (ie PC case fans) tend to generate quite poor static pressure. Centrifugal fans (ie slot fans) are generally much better at producing high-pressure air (which is necessary to overcome the resistance of a small heatsink with closely-spaced fins).

[diver]

I don't know if it will work with your particular card, but you could try to slow the fan down with Riva Tuner. That way it would only ramp up when playing games.

Or, you could try to place a resistor on the fan. About 100 ohms will probably be enough, but YMMV.

Neither of these techniques will compleely silence it, but it might be enough to keep you happy, depending on how quie the rest of your system is.

If all else fails, a cooler is only about $30.

[mentawl]

I've modded my 7800GS in a similar way to that you suggest miller. Check my post at http://forums.silentpcreview.com/viewto ... 013#259913 for pics and stuff. Works really well on that card, and it draws a fair amount of current, all things considered.

[Le_Gritche]

Why not just remove the HSF cover panel, disable the onboard fan, and position an 80mm Panaflo kind of up close at the heatsink surface.

Anyone here even tried anything like that? Or seen an implementation?

You should look the thread called Passive 6600 reaching 100c...
flyingsherpa did exactly that and posted a picture of it. You can find his message around the middle of the page.

[miller]

Thanks for all the comments and links, everyone.

Going to experiment on this next weekend.