Alphacool’s VPP755 Pump Sounds Too Good To Be True, Better Than D5 In Every Metric

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urbanj

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Looking forward to a review/comparison with the D5, as I was a few weeks away from ordering parts for a water cooling loop once my new case arrived.
 

alextheblue

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It accepts a PWM signal and when such a signal is provided, uses that to determine at what speed it should be running. How is that not "PWM controlled"? Plus they provided an easy way to cap peak RPM without additional software.

Edit: Watch the embedded video for details.
 

jasonkaler

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Wow, it makes me wonder how bad the original design was that it could be improved on by a whole 50% efficiency.

That means that originally, at least half the power was consumed by forces other than actually pumping water.
 


Lets stop and think a sec. (hard for a Monday morning, or a Sunday morning for that matter.)

50% improvement.... say (unit just randomly chosen) it pumped 100 mL per second. The 50% improvement would be 150 mL/S. From the improved position, the old unit is 1/3 less efficient. I do understand your point though and wonder where the losses were.

 

KD_Gaming

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Im surprised none of you have noticed the flow rate... 350l/h. A D5 with a ek top puts out 1500l/h with a 3.9m pressure head. Overall ill take the D5 anyday over this.
 

urbanj

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...maybe we haven't noticed it, because we have been looking at charts that show the D5 below the VPP755.
If you want to link what you're looking at maybe?
 
That xtremerigs review said max output is around 750 - 800 LPH, so it would appear the 350 is underselling it. However, putting the PWM cable as a tail on the Molex seems a mistake to me. It works fine if you have a central fan controller that everything plugs into in one place, but if you use the PWM directly off your mboard, that means you have to route a Molex there as well.
 

alextheblue

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I mostly see that as a non-issue. They need that 12V line regardless, the PWM is just for signaling. So either way it needs two cables if you intend to use PWM. If routing is your issue, they have cable extensions (PWM too naturally) so you can neatly pin and route however you want. If they made it a separate cable (added a PWM header to the unit) that might have been a little nicer but if I'm building something advanced enough to warrant a VPP755 I'm not going to let a little wire or two bother me. :D
 

jasonkaler

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Lets stop and really think. Here's the line from the article:
"It also has the bonus of drawing 50% less power".
Your move...

Btw, the power was being lost mechanically, being converted to vibration and noise. Easily happens if you don't align poles properly in an electric motor.
 
You do realize a motherboard 4-pin header supplies 12V, right?

No, you can get sufficient power from the mboard header alone. Older D5 pumps draw 25W or more at full load so the extra power capacity of Molex and SATA leads was necessary. However the VPP is supposed to cut that almost in half ( specs list 14 W max draw ). That's well within the power envelope of a mboard header.

Great, one more thing to buy. I don't know about you, but generally I don't buy things if I need to get something else in order to make them work correctly or efficiently.

Wrong, they already have the separate cable, it's simply under the shrink wrap along with the power leads. Instead of simply wrapping each cable separately, they went the more complex route of wrapping both halfway, them splitting them and wrapping the ends separately.

Give a thought to how most computers are laid out. Mboard vertical in the case, PSU underneath it. The PWM fan headers are almost always at the top of the board ( most system/chassis fan headers at the bottom of mboards don't support PWM ). So Molex comes from the PSU at the bottom, but PWM headers at the top, and you've got maybe 6" or cable to span that. Instead you've got to route an additional PSU lead up to the top of the case. This would be less an issue if they used a SATA power lead since you might have drives at the top of your case. But fewer PSUs mix SATA and Molex on the same lead these days.

And having that additional 3-pin tail off the 4-pin line is absolutely pointless since you can plug a 4-pin onto a 3-pin header.

One thing about people building high-end machines is they tend to like them looking nice and uncluttered. It may be a minor frustration, but having one more complication to cable routing does wear you.
 
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