What CPU can I use that requires a heatsink only without a fan!?

[mechBgon]

I'd go with the Alpha 8045 too. Lots of people have made the observation that a larger fan produces a lower-pitched noise that's less noticable even if the dB rating is the same as a smaller fan. I would think that the 24cfm output of a Panaflo L1A would be enough for any of the AthlonXP's at default speed and voltage, with the PAL8045 heatsink and a good thermal-interface material (Arctic Silver II). If you're in doubt, then get a Panaflo M1A and make a 12V-to-7V converter to run it at 7 volts. If the temperature is higher than you'd like, then you can always go back to 12V.

I've used the Adda 16dB 60mm fans, and found that the motor makes a bit of a whine which is noticable in a really quiet room. Dropping the voltage from 12V to 7V pretty much eliminates that, but cuts back the airflow. Fine for cool-running Coppermines, but not Athlons. The 60mm Panaflo L1A's make more airflow noise than the Adda but they seem to move more air too.

Another fan that really impressed me was the Enermax thermally-regulated fan. I got some of them from Newegg.com and for $6, you can't beat it. They include fan screws, a chrome grille and a 3-pin-to-4-pin adapter, and if their probe is at room temperature, they run even quieter than an L1A in my opinion. Very pleasant. And you can use hot glue or something to attach the probe to the base of your heatsink, so the fan will pick up speed a bit if the heatsink is getting hot. Seems like a good match to the PAL8045.

 

[Ausone]

<< I think most hard drives make more noise than good 80mm fan. So if you are building a system with a normal EIDE hard drive, you can not get absolutely quiet system. So don't let this noise issue limit your choice of CPU. >>

You are right about HD often being the greatest source of noise, but that doesn't make quieting other noise sources futile. I mentioned how you can quiet HD in my previous post in this thread, so let me note here that even if Barracuda IV still remains to be the noisiest, it makes sense to reduce other noise since that minimizes the noise increment from other parts, hence contributing to the total noise reduction.

From the perspective of building a really quiet, almost silent machine, it does make sense to choose a CPU that requires less cooling hence enables you to use a HS with the quietest fan or even a _fanless_ HS. On the other hand, if one puts more priority on extreme quietness than extreme performance, one sees little reason to choose a hotter running CPU over a cool running CPU for not-so-tremendous performance gain. You may be able to build a reasonably quiet machine with Athlon XP, but why make it harder to make your machine quiet? One can just as well say, "Don't let your choice of CPU limit the extent of noise reduction".

With really high frequency of today's processors, it doesn't make critical difference for users with average processing needs whether one chooses Athlon XP or Tualatin Celeron. Sure, there is a noticeable difference that may be significant in terms of numbers, but if Tualatin Celeron that runs at over 1GHz gets your job done and if you want a quiet machine, it's really hard to find a convincing reason to get Athlon XP or PIV, both of which are often more expensive than Tualeron. Tualeron is available at 1, 1.1, 1.2 and 1.3 GHz, and you can overclock it to 1.5 GHz with less heat than any of Athlon XP or P4.

Of course, if you really need the power of Athlon XP or PIV, then that gives a sufficient reason to choose it over Tualatin PIII/Celeron. Sure, it all depends on your priorities. But I think people are a little too much obsessed with the extreme CPU power.

 

[BlackOmen]

My friend is doing an IT intership and was allowed to keep some hardware after their last upgrade. One of the goodies was a P2-400 (100mhz fsb) that used a heatsink only.