Introduction

As you should be aware if you are a regular visitor to BlueCouch, I have started a quest to create a Silent PC from common components. I want to avoid having to use acoustic foam and the likes. Today I am working on reducing case heat by installing a more efficient heatsink.
In theory a heatsink that dissipates heat more efficiently will allow me to use a low voltage fan to cool it. My weapon of choice is the Thermalright SLK-800U purchased from Below-0 in Queensland. To reduce the noise of the old stock AMD heatsink fan I have purchased
a Panaflo L series 80mm fan, a 3 pin tail, a Zalman fanmate and some Arctic Ceramique thermal paste from PcCaseGear in Melbourne.

 

The SLK-800U

The SLK-800U is a real enthusiast heatsink. This baby is copper fins soldered to a copper base. Why copper? Copper is more conductive than the standard aluminium
heatsinks. The downside is the price and the weight. To get around the weight issue, the SLK-800U mounts to your motherboard using 4 standoffs that screw through the holes around your CPU socket. If you are considering buying this heatsink make sure you purchase a motherboard that has these holes.

The heatsink is weightsand wighs an absolute ton. On the left is the standard PR shot of the heatsink from the website.

Dimensions:

L87 x W56.4 x H48 (mm) - Top, without fan

L67 x W81 x H45 (mm) Bottom, without fan

Weight: 550g

For such as sexy beast, the SLK-800U comes in a boring old cardboard box. This does help keep the price down though, given it is such a high end part. It’s what comes in the box that you want, so, have a look at what you get.
You get the heatsink, two sets of clips which you use for mounting different height fans, thermal adhesive, mounting screws, mounting brackets for Pentium 4’s, mounting poles for AMD Athlon’s feet to stabilise the heatsink on the core,
and a bracket to fit under your motherboard into which you screw your standoffs. Wow!

The third picture shows the standoff’s inserted into the motherboard heatsink mount holes around my socket. The motherboard I am using in an Asus A7v-266.

The Panaflo

Ok, now that we have the motherboard prepared, time to have a quick look at the Panaflo L1A series 80mm fan. The panaflo fans are the quietest fans I have ever had the pleasure of playing with. The L series fans are low speed,
and push less air around than other 80mm fans, but this is all I need for my big sexy SLK-800U heatsink. Because the SLK-800U is so good at transferring heat from the core, I don’t need to have the fan running at 12v, or pushing a lot of air for it to do its job.
This makes the panaflo and ideal candidate, given I am not overclocking, I am after silence.

For the record, here are the specs of the L1A series Panaflo fans:

Air Flow 24 CFM

Fan Speed 1900 RPM

Power 1.2 W

Bearing Type Hydro Wave Bearing

Fan Size 80×80x25 MM

Noise Level 21 db

Connector Untailed

The last note is important. When you buy a panaflo, you also need to buy a panaflo 3 or 4 pin tail. the 3 pin tail is for a motherboard header, and the 4 pin is a molex connector. Ok, now that that is all covered, here is what it looks like attached to the top of the SLK-800U. Note how I have the fan upside down. This is blowing
air down onto the Heatsink. I have since been experimenting with it sucking off the heatsink, which increased the CPU temps fractionally, but decreased my case temps. Another trade-off.

Zalman Fanmate

Ok, earlier I mentioned that I didn’t need 12v to the fan. This will raise an interesting question for many of you. How do I run a 12v fan at less than 12v? The easiest solution is to go out and buy a Zalman fanmate. Now reducing voltage reduces fan rotation speed, and as a consequence reduces air turbulence noise. On the other side of the equation is increases the temps of both the
CPU core, and the motherboard. Combined with the SLK-800U I can run the fan at about 7v, have less noise, and be running lower temps than I was with the stock AMD Heatsink/Fan combo.

So how dos it work? The Zalman fanmate sits between the Motherboard and the Fan, and has a little knob that you twist to reduce the voltage going through to the fan. Lower voltage = lower speed = lower noise.
And when you are doing it to one of the quietest fans in the world, it makes it completely inaudible.

The Arctic Silver Ceramique

Instead of using the standard thermal grease that comes with the SLK-800U I decided to fork out some cash on the new Arctic Silver Ceramique paste. This tuff is meant to be not electrically conductive, so if
you put a bit too much on, and it spreads onto the circuitry on the top of the chip, you don’t short it. Better to be safe than sorry right. I won’t bother with any photo’s or anything like that as you can search the
web in a million places, and read all about it.

All assembled

Ok, I have taken this shot with everything attached, but still outside of the case. This will give you a much
better indication of the size of everything.

Results

Well the biggest result for me is the reduction in noise. This thing is completely inaudible inside my case. The only thing I can hear now is a slight hum from the PSU. This is not fan or turbulence noise, it is electrical noise. This noise is not huge, and is inaudible from 5 meters away.

For those of you who are worried about temps, I have some before and after temps for you. All of these temps are at idle load in ambient room temp of 18c.

Now the temp changes aren’t huge, but I have no noise. This proves that with a little cash (about $150) and some time and effort, you can remove all that pesky noise.