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DDE8 Thermal Monitoring unit

Heat sensitive fan controller reviewed

Dark blue icons of video game controllers on a light blue background
Image credit: Eurogamer

- Dragon DirectPrice - £30 including VAT and postage

Overclockers Utd.

Everyone knows that heat is the overclocker's worst enemy - as your clock speed rises, whether it is your CPU or your graphics card that you are turbo charging, more heat is generated by it.

The cheapest way to ensure good stability and juicy clock speeds is to simply promote good airflow within your case. The addition of even just a single 80mm case fan can slice over 10 C off your temperatures. The next stage is the basic "one-in / one-out" principle to keep the air inside your case nice and fresh. Some even go to extreme lengths and add 3, 4 or even 6 large fans to help keep temperatures down. Both and PowerComputing sell such cases here in the UK.

Unfortunately, as one adds more and more fans, the noise they collectively generate increases. Hush for a minute, and listen to the sound coming from your PC. For many readers, there is just a faint background hum of the fan inside your power supply, and a distant rumble from your CPU fan.

Add a pair of 80mm fans though, and the noise level rises. You find it hard to concentrate, and often resort to playing MP3s while you work in order to drown out the noise from the fans. As soon as you start messing with 120mm fans things start to get very loud indeed.

The solution is to only have the fans switched on when they are needed. For the electronically inclined, you can order a FanBus from Cliff, or even attempt to make one yourself based on the numerous DIY guides floating around the Net. But as cool as it looks, with its blue LEDs and everything, the FanBus is still a manual solution. It is up to you to monitor your temperatures using Motherboard Monitor, and switch your fans on and off to suit.

The Dragon Cooler

Enter The Dragon

For those people with a little more money to splash around looking for a more autonomous solution, I recently stumbled on to a product that should suit you down to the ground...

Introducing the Dragon-Direct DDE8, or Dragon Cooler as I call it. Designed and built in Wales of all places, it's a fully automated thermal monitoring and fan management system, which monitors the temperature of your CPU, graphics card, hard drive, or whatever you choose, and then switches your fans on and off according to your preset temperature range.

The unit comes as a complete kit - you get two motherboard-type thermal probes, power leads, a pass-through cable, even four screws to mount it in a spare 5.25" drive bay. Build quality is impressive - a pressed sheet steel cage houses the electronics, and the front plastic bezel is solid enough.

The model I received can take two separate thermal probes, but there is an eight-probe version if required. There are two 40mm fans incorporated into the unit which can blow or suck depending on your requirements, and they are filtered either way, which makes a handy addition for those with dusty houses, or pets. The clever bods at Dragon Direct have also specified the unit to drive one external fan.


For such a simple principle, it's amazing how much excitement is generated when I show the Dragon Cooler to friends. The fan is off. Pinch probe with fingers. The fan switches on. Ooohh. Release the probe. The fans switches off. The crowd goes wild!!!

Having lived with the constant hum of three 80mm case fans for nearly a year now, the asking price of £29.99 is a small amount compared with the peace I now enjoy with the fans switched off most of the time. They stay silent when I'm word processing, but then kick in when I get down to some heavy-duty deathmatching and the temperatures start to rise. When I quit Quake 3 the fans keep running until the temperature is down to normal, and then switch themselves off again. Heavenly.

Oh, and did I forget to mention that the LCD screen is backlit? Yes, it glows an eerie blue when powered, making the display easy to read even in low light conditions, and it looks dead impressive at LAN parties.


While it probably seemed like a good idea at the time, and was a necessary addition for non-hardcore customers, the two 40mm fans inside the unit are pathetic. They might be silent, but they shift so little air it really isn't worth bothering.

The good news is that these fans are not hard-wired into the PCB - they use tiny 2-pin connectors on to jumper-type pins on the board. So of course the first thing that a hardcore user will want to do is to unplug them. When Phil from Dragon-Direct said "Sure, try it, but it will invalidate your warranty", that was like a red rag to a bull.

The personality "flaw" of the true overclocker is to never be satisfied with the normal spec of anything. Celeron II 566 guaranteed to 850MHz? Gotta run at 875Mhz! My Elsa Erazor X is cooking along at 165Mhz core and 185Mhz memory. The DDE8 was designed and is sold to drive the two 40mm fans and a single 80mm fan only, but that wasn't about to stop me...

So, having removed those pitiful weenie fans, I proceeded to wire the Dragon cooler up to all three of my 80mm case fans. No problem. Determined to push the boundaries a little further, I whipped out my brand new YS-Tech 120mm fan. This bad boy is rated for 120 cfm, and pulls so much current that you will blow the fan header if you attach it to your motherboard for power. So in it goes, and guess what? No problem!

This is the reason why I bought the DDE8 - I wanted to get my case temperature close to ambient air temperature without the constant ear-bashing from fans capable of shifting more hot air than your average politician.

Room For Improvement

Despite the two thermal channels, and capacity for up to eight, the fans will switch on when either probe exceeds the set temperature. And since there is only one channel for power, it's a case of all or nothing when it comes to fans - they are either all on or all off.

In an ideal world (and possibly something that Dragon-Direct could work on in future) you would be able to power separate fans from separate probes, allowing you to zone your case and cool it appropriately. If this wasn't possible, I would really like a dual-stage monitoring system, where a set fan would engage when you reach a certain temperature, but if the level continues to rise, another fan would kick in.

In the meantime, I have a single 80mm fan on all the time, and then I have my remaining two fans switching on and off as the temperature fluctuates.


The DDE8 is the only unit of its kind available in the UK that I am aware of, let alone at the stonking price of just £30. While it does not allow the individual fan control of a FanBus, its autonomous nature allows you to concentrate on your work (or play), and leave the temperature monitoring to the experts.

For anyone with more than two fans in their case, and certainly anyone who is annoyed by the constant rumbling this causes, I highly recommend this product to the point of labelling it as an essential purchase.

Temperature freaks rejoice, for there is a God .. and he lives in Wales.


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