[Cathar]

Okay, just to keep all this info in a clearly labelled single thread:

The new Laing D4, which can be easily identified with its black, rather than blue, pump body, and a red 5-position speed dial on the back. Feedback from various water-cooling equipment retailers have informed that the pump will go by the MCP655 moniker from Swiftech in order to clearly designate the now quite different pump from the older Laing D4 (sold as the MCP650).

Some pictures of the new pump are here:

Back of pump

Closeup of speed-dial knob - shown in the #5 position

Isometric view of pump from front left

Isometric view of pump from front right

Just to avoid confusion, the pump label says:

Volts: 8-24
Watts: 3-33
Amps: 1.4

The pump is rated for up to 60C fluid temperatures, and a peak of 50PSI internal pressure. The 50PSI operation limit could only be reached in practise if a second pump was deployed before the D4's inlet providing >45PSI of pressure into the D4 pump, so this is not something to ever be concerned about for most everyone.

The big thing about the new D4 is the lack of noise. Anyone who's used one of the older D4's will know that they emit quite a loud and annoying buzz-like whine, some more loudly than others, but overall it's not a pleasant sound. These new D4's are now extremely quiet - quiet enough to challenge an Eheim 1250. This is not to say that the pump is silent, but it is quieter than almost any disk hard drive anyone cares to name that people put into their computers. Of course the pump does vibrate very slightly, and if it is allowed to vibrate or resonate against something then it can be quite noisy, but this is an issue that can be fairly easily solved by employing a small measure of vibration dampening.

Performance

I am still in the process of assessing the pump's performance characteristics, but I will say this in summary: it is significantly stronger at its highest speed setting (#5) than ANY prior Laing D4.

Right now all I have done are some peak pressure tests (how far vertically it will push a column of water), and the power draw under these conditions. My results are as follows:

12.0v input
Setting, Pressure, Power Draw

#5, 4.10mH2O, 21.0W
#4, 3.05mH2O, 14.5W
#3, 2.25mH2O, 11.0W
#2, 1.40mH2O, 7.0W
#1, 0.60mH2O, 4.0W

The speed dial on the back in actually a continuous type dial. Meaning it can be set inbetween whole values.

One very interesting observation was seen when attempting to over-volt the pump. I tried pushing up the voltage to 13.5v, and the peak dead-head pressure went to 4.2mH2O. I ramped it up to 16.0v and the peak pressure remained the same. I dropped the voltage down to 12.25v, and found that above this point that the peak pressure of 4.20mH2O did not change, and below this point is where it started to drop away. Dead-head power draw amperage remained constant as well for voltages between 12.25v and 16.0v, meaning that power draw was just ramping linearly with voltage above 12.25v.

Let me say all that again more clearly:

There is no point feeding the pump more than 12.25v, it simply will not go any faster.

I would imagine that this has been implemented within the pump's controller circuitry.

By the same token, decreasing the input voltage does not have a major effect on the pump's performance. Pressure does go down, but does not follow the same pattern as other pumps. With most other pumps the amperage drops off as the voltage is dropped, but not so with the new D4. Amperage remains the same and the pump remains pushing water to a vertical height of 2.5m even when just above its measured stall voltage of 7.5v. Below 7.5v, the pump just stops.

Again, there appears to be no point in either over- or under-volting the new D4. Just feed it 12v and adjust the speed on the knob on the back.

I will be conducting further tests to test for heat dump and generate some PQ flow curves. I'll be doing all these at 12v, since this is now obviously what the pump was designed for, and it's also the most relevent measurement point now given that most people will simply be running the pump off the 12v rail of their PSU.

[Senater_Cache]

Excellent read once again Cathar.
I am looking forward to implementing this pump in my new setup. (Now all I need is a G )
Oh btw, any news on different "tops" with say, larger or smaller OD barbs?
Hopefully it will be available in 3/4 OD.

SenC.

[nikhsub1]

Hehe, now to overclock the pumps internal voltage settings

[MVC]

I wonder if I can exchange an old noisy one for a new quiet one? I doubt it

[itchy5]

nice read cathar, cant wait to see some real tests

[IYIENACE]

Yes thank you for the information and please let us know how it compares to the others.

[blt111]

anyone want to buy an mcp650?.....

i guess the value of my 650 has just dropped about $50

[edit] anyone know of a distributor for the uk? i don't think they're available here yet

[Hoot]

Darn, I had a review written for the one I got for testing for the past two weeks, but was waiting for Swiftech to announce its release. Since the Cat's out of the bag, it is a very nice pump. I don't have any other DC models to compare it to, but to my ears, it is very quiet. You certainly can't hear it in my tower, with the covers on. It did not lower my temps below what my Eheim 1250 produced, but the DC feature is nice for people who don't want to wire up switched AC inside their case like I did. The best thing is it's small size compared to the 1250. You have a lot more options as to where you can mount it.

Hoot

[Shaotai]

Originally Posted by Hoot

Darn, I had a review written for the one I got for testing for the past two weeks, but was waiting for Swiftech to announce its release. Since the Cat's out of the bag, it is a very nice pump. I don't have any other DC models to compare it to, but to my ears, it is very quiet. You certainly can't hear it in my tower, with the covers on. It did not lower my temps below what my Eheim 1250 produced, but the DC feature is nice for people who don't want to wire up switched AC inside their case like I did. The best thing is it's small size compared to the 1250. You have a lot more options as to where you can mount it.

Hoot

Ah ha! This must be the top secret quiet pump you had mentioned in other posts. (The quiet pump thread)
After someone posted some pics of the MCP655 a few days ago, I was guessing this was the pump you had from the initial reviews...
So where is your review?! Let's get it posted!

[OCS911]

how is it compare with MCP600 aka 50Z?

[Cathar]

Originally Posted by Hoot

Darn, I had a review written for the one I got for testing for the past two weeks, but was waiting for Swiftech to announce its release.

When news reached my ears that resellers were already shipping the pumps to customers, that's when I decided to post about it.

When I received the pump I had asked for guidance from Swiftech on when I should post about it, and got none. Out of courtesy I at least waited until resellers were talking about it.

[Hoot]

Yeah, silly me, I was relying upon the Swiftech Web Page...

Not much to improve upon over Cathars post. It's a good pump and a fine first DC pump for me.

Hoot

[wfarid]

.:subscribed:.

[Sneaky]

besides noise, how does this compare to the MCP650/D4?

[Cathar]

Originally Posted by Sneaky

besides noise, how does this compare to the MCP650/D4?

Peak flow is a touch higher with the MCP655 (no hard figures yet - but it is). Peak pressure is higher (4.2mH2O with MCP655 vs ~3.3mH2O with MCP650).

Extra flow/pressure does not come for free though. If we set the dial on the back of the MCP655 to the #4 position, it fairly closely mimics the old MCP650 in terms of pressure/flow/power consumption. When you move to the #5 (more powerful) position, the pump is sucking down more power.

Overall, when set to full speed, it is clearly a more powerful pump than the MCP600/D4 ever was, when run at 12v. Would need to run the older D4's at 14.0v to reach an equivalent sort of pumping power/effect - but then the noise becomes even more of an issue.

I'll be running some system flow tests soon.

[Shentx]

Once they name it as the MCP655 on the reseller web pages, do you think its going to cost the same as the MCP650, or are they going to stop making the MCP650's?

[Sneaky]

so these are already shipping to retailers, and will be available to the general public soon?

cause i'm probably gonna be picking 2 of these up to run in series for when i get my WC back up (G5 baby!)

[Acurax]

I'll probably be getting 2 of these in series as well

[cetoole]

Cathar: Any idea how the heat dump of the MCP655 compares with the MCP650/600/350?
Hoot: Were you testing with the impingment block? Kinda suprising that the temps wern't lower than with the 1250.
Have either of you opened it up yet?

[Hoot]

Originally Posted by cetoole

Cathar: Any idea how the heat dump of the MCP655 compares with the MCP650/600/350?
Hoot: Were you testing with the impingment block? Kinda suprising that the temps wern't lower than with the 1250.
Have either of you opened it up yet?

Yes I was and am using one. I don't know why there is no discernable difference though. When my G5 ships (Ahem!) it'll be interesting to compare it to my clone.

Hoot

[inkfx]

www.crazypc.com sent me this pump on accident instead of the MCP-650 that I ordered. Cant wait to get my system hooked up. Im getting some distilled water tomorrow along with some antifreeze.

[OCS911]

this pump also draws alot of heat, double amount of MCP600 can't argue with that since it is more powerful than any previous version, wait for review too especially dual pump in series review

[Cathar]

Originally Posted by cetoole

Cathar: Any idea how the heat dump of the MCP655 compares with the MCP650/600/350?
...
Have either of you opened it up yet?

MCP655 looks identical internally in every respect to the MCP650, both in the wetted end, and the "motor/stator", with the exception of the different electronics controller and the knob on the back.

If the MCP655 has a significantly different ratio of input power:heat dump to the MCP650, then I'll be one surprised person. I will of course measure it to verify.

I also have an MCP350 here, but have yet to put it through anything more than a cursory "does it work?" test.

At 12.0v, the MCP600 typically drew around 12-13W of power when in a setup, and passed around 70% of its electrical power draw into the water as heat. (eg. ~8-9W heat dump).

At 12.0v, the older MCP600 typically around 18-20W of power when in a setup, and passed around 90% of its electrical power draw into the water as heat. (e.g. ~16-18W heat dump).

At 12.0v, the MCP655 when at full speed (#5 position) typically draws around 24-25W of power when in a setup. Remember, the power-draw numbers that I posted in the first post were at dead-head, which is where pumps draw their least power.

[Joe Camel]

Originally Posted by Cathar

At 12.0v, the older MCP600 typically around 18-20W of power when in a setup, and passed around 90% of its electrical power draw into the water as heat. (e.g. ~16-18W heat dump).

with such a HIGH % of pass-through, is COOLING the pump worth looking into?

to sum it up, i drilled holes into the pump motor section and cooled the MOSFETS etc that drive the pump. i was able to take 5.9 F out of the heat input. im sure adding a HS to them could help a little more.


PS nice to see you around again Cather (glad your feeling well again )

[Sneaky]

so how much longer till we'll see these in stores?

[blt111]

Originally Posted by Sneaky

so how much longer till we'll see these in stores?

i was under the impression they are already shipping in the US

[inkfx]

Well I have been leaktesting my system for close to 24 hours now with this pump. This pump is VERY quiet. I have to put my ear up onto it to even hear the little buzz it makes. When I touch it I can tell its a bit hot. This is my first w/c setup so I cant really compare its heat to any other pump.

[tyrant222]

is swiftech going to replace the 650 then? if people are getting the new version (655) in just about every case ive seen it seems that they will just phase out the 650.

[Hoot]

One good thing you can do, which I've been doing with my pumps all along is to mount them in the exhaust stream of your radiator fan. Mine pulls cool air in from outside the case, and the pump sits in front of its exhaust. Touching the pump, it is cooler than skin temperature, so I'd imagine it's not contributing as much heat to the water as if it were sitting in relatively still air. Something to consider.

Hoot

[wannaoc]

Is Swiftech going to keep the black casing or paint it blue to keep with thier color theme? Just wondering because my local reseller has it labeled the 655 but show a blue casing on the pics.