articles
FORUMS!
links
contact

PC Database

Folding Team

SETI@HOME Team
RC5 Team
Genome Team

OCAU chat

A couple of months ago I received a single-fan water-cooling radiator (review here) from Senfu and, with some modification, hooked it up into my own water-cooling rig (details here). Recently I recieved the whole kit from Senfu and have spent a month or so hooking it up to various processors. You have to give Senfu some credit for making a kit like this at all. Water-cooling PC's has always been something of an arcane art, practised by an elite (and some would say dangerously speed-obsessed) few. It's fun going to wreckers for radiators and making things, adapting what you have or can find and constructing a frankensteinien creation which lets you massively overclock your machine. However, at some point the technology has to enter into the mainstream - the pioneers have proven the technology is viable on the small scale of PC's (it's been in mainframes for decades) and it's not surprising that mass-produced kits like Senfu's are starting to appear on the market.

Senfu's kit is sold as a few separate parts, in their own boxes. These can all be purchased separately so come with their own instructions etc. In the first section of this review I will examine each of these parts in detail - the twin-fan radiator, the pump and of course the core of the system, the water-jacket itself. Senfu's waterjacket is quite clever, in that it comes with mounting equipment for socketed CPU's such as mendocino celerons and coppermine p3's, but can also be used on SECC2 CPU's (slot1 P3's) and SECC1 cpu's (Pentium2's and Athons). I have experimented with the Senfu kit on a few different processors and I have devoted a section of this review to each processor type.

Twin-Fan Radiator
A basic problem with water-cooling is, what do you do with the heat once you remove it from the CPU? Obviously, you want it out of your system and into the surrounding air. In order to do this you need to expose the water to lots of ambient-temperature air. This is best accomplished by using fan-forced radiator with a combination of high surface area and high airflow. The unit Senfu provide with this kit is a monster, fed by two 80mm fans and containing, in my estimation, over 3.5M of tubing. It's the equivalent of two of their single-fan units side by side and judging by the performance of the (modified) single-fan unit (read my previous review here) I would expect this to be capable of coping with all but the most extreme peltier-assisted watercooler.

The fans themselves are powered by 2 passthrough connectors which can be joined to form a single pass-through. This is something of an interesting design decision by Senfu as it implies they intend you to mount it inside the case. If you're intending to mount the entire water loop inside your PC, you may have some serious size issues with this unit, at 205mm long, 105mm wide (including the fans) and 105mm tall. You'd be best off mounting it on top of your tower or perhaps in a separate enclosure below it, which might involve modifying power leads to reach the fans. Keep in mind you want to have the minimum vertical distance traveled by the water in the whole system, though. People have batted this one back and forth in the forums about whether the water height should make a difference or not, but all I know is, if I lift the radiator, the flow rates drop. So mounting the radiator on top of your fulltower (maybe a foot or two above your CPU) may not be a great idea. The very small diameter water pipes are a source of immediate concern to me, as they look like they would impede the flow of water considerably. Senfu use 4mm internal-diameter tubing in the entire kit. I can't help but think the system would get better flow rates with larger tubing. We'll see how it goes in the testing.

Senfu have included a roll of waterproofing tape and some cable ties. It also comes with some sticky rubber feet to raise it off your desk a bit and a sheet of instructions. In fact, the instructions included with this part are much clearer than those included with the water-jacket. Strange, because this is the easiest bit to understand - you don't really need an instruction sheet at all. Connect the fans, connect the water-tubing (flowing from bottom-to-top to help air-bubbles escape) and off you go. In operation the unit is fairly loud, those two fans move a serious amount of air and you can definitely hear them in action. Another quick note - be careful when bending those inlet and outlet tubes, if you do - the bases are thinner than they look and it's not too hard to warp the tubing they're mounted onto. If you're after more info on this unit I really recommend reading my review of the single-fan unit as they are functionally very similar.

Water Pump
Another important part of the kit is the pump. Senfu originally shipped this kit with a different pump, the L200. This was a 110v unit fitted with a USA-style plug so was less than useful in the 240v environment here in Sydney, Australia. During the course of testing, Senfu sent me the motor they are using from now on, the L700. As well as being available in a 240v version with an Australian plug, these are the differences:

Suffice to say, you want the L700 if you get the option - it's a much more powerful pump. It's also quieter than the L200. Both need to be submersed in a reservoir in order to keep themselves cool and to draw water in. The opposite of this kind of pump, an in-line pump, has an inlet and an exhaust valve which means the unit just sits at some point in the tubing and you only need enough water to fill the tubing, jacket and reservoir. A car's fuel pump is a classic (if bulky) example. They're generally quieter than submersible pumps but tend to be much more expensive. A submersible pump deals better with air-bubbles in the system, too, as they collect in the reservoir. Submersible pumps are common in fishtanks and garden ponds - they will add a small amount of heat to the water and make a noticeable buzzing, fluttering sound. This unit is not incredibly loud - noticeably quieter, for example, than the Rio 800 I used in my original water-cooling system. It's not as loud as the fans on the radiator. The pump is not silent, however, and you might want to consider surrounding your reservoir with sound-proof foam if the noise is going to be an issue for you. This brings to light a fairly serious failing of the Senfu kit - no reservoir is included. If you're not too fussed about dust, insects and space you can just use a plastic bucket, as I do, but it would make the kit much easier for the end-user if included a reservoir that seals around the pump. Without it, their kit is not really complete as sold.

L700 Water Pump

I'm not sure exactly what options are available in the way of power plugs - you'd be best to specify what you need on your order. Otherwise, presuming you get the correct voltage model, it's fairly trivial to cut the cable off and solder a suitable plug on. Get an electrician to do it if you're not comfortable with lining up the correct wires.