Stock Athlon64 fan quieter than Zalman 7000A AlCu??!

[dimva]

From the advice of this forum, I immediately installed the Zalman 7000A AlCu instead of the stock Athlon64 fan when I built my new system. However, I was curious as to how much louder the stock fan was.

It turned out to be quieter. At the 5V setting, the zalman fan was as quiet as a whisper, but the stock fan was virtually silent. At 12V, the zalman fan was noticeably loud, and the stock fan was a bit louder than the zalman was at 5V.

I don't know much about this, but I thought the Zalman was supposed to be (one of) the best hs/fan combo(s). So I'm guessing that the Zalman is better for some reason:

• The stock fan pushes less air. I don't think this is true because I could feel much more air movement with my hand in the stock fan than in the Zalman (I could barely feel the air moving at all).
• The stock hs/fan combo doesn't cool as well. Since I haven't tested the stock hs/fan I don't know for sure.
• The stock fan will be noiser once it's mounted onto a chip. When I was testing these, the stock fan was not attached to anything but the heatsink and the Zalman was on the chip. I don't know why this would be true, but it's the only other reason I can think of.

Or, my Zalman is broken. If this is the case, what should I do?

If anyone else has noticed something similar or has any reasons as to why this is the case, please post here about it.

[Rusty075]

The stock HSF is thermally controlled.

Since it wasn't on a chip, it was running at its lowest speed, a speed that it would never actually run at while in use.

The thermal control of the HSF goes hand in hand with the A64's "cool & quiet" feature. (If the fan didn't slow down as the heat from the CPU dropped, what would the point be of having the wattage decrease?)

Try heating the stock HSF and you'll see the fan RPM ramp up.

[wumpus]

Yeah, that's the same reason we USED to think the Seasonic Tornados were "quiet". They are quiet, under trivial load. Once you get a normal medium to high end system load in there, the ps fan quickly ramps up to annoying volume levels..

[Talz]

Just mount both and see what sound level is needed for comparable cpu temps. I'll be shocked if the zalman doesn't end up with a cooler cpu at the same noise levels though.

[dimva]

^^ Too late/too lazy to do that now. Might try tomorrow.

The stock HSF is thermally controlled.

Since it wasn't on a chip, it was running at its lowest speed, a speed that it would never actually run at while in use.

The thermal control of the HSF goes hand in hand with the A64's "cool & quiet" feature. (If the fan didn't slow down as the heat from the CPU dropped, what would the point be of having the wattage decrease?)

Try heating the stock HSF and you'll see the fan RPM ramp up.

I thought the fan speed was controlled by the voltage coming from the connector on the motherboard.

The stock fan is pretty nice. I'm going to use it to cool the radeon9800pro, along with zalman's vga cooler. When it's running on high it's still very quiet and you can detect quite a breeze coming from it with your hand.