@Martin, (or anyon else good with pumps, por, and pump life)

[Slave1974]

Ok, here we go guy, you all guided me to a very succsful build. I am now on the grind again.

I currently have MCP 35X, 360 Rad, Reservoir, 7/16"ID tubing, AMD 965 (4300mhz) Swiftech GPZ, HD 5870 with Swiftech Komodo

I am adding a 240 rad, a second pump and a bigger reservoir, second 5870, with Swiftech komodo.

I read for temps, I should un parallel of the GPU's.

I am swapping the 35X for two DDC-1T's with the DIYINHK 18W PCB's. I ran a MCP 355 until it died in 2 months, but it was never loud to me.

I plan on running the XSPC dual bay res/pump top. I will run one pump into the other in series.

Am I understanding correctly, that too high flow kills these pumps? Should I run the GPU's in series to add some restriction to slow it down to save the pumps?

Am I being paranoid after my first pump died?

Is there a better bay res/pump top that work better? I just don't trust that koolance one with the pumps being upside down.

Thanks guys.

[Martinm210]

If I understand right the MC60 is pretty close in restriction to the Komodo.

Assuming MCR like radiator restriction, I think your flow rate is pretty strong and good with just a single pump. With a 35X I'm guessing greater than 1.5GPM.

Even adding an MCR220 and second Komodo would still be almost 1.5GPM.

So, it seems as though you don't really have much restriction and have been running pretty high flow rates. High flow rates do increase pump heat, but you can mitigate that heat by either turning the pump down and/or adding a heatsink to the base or fan cooling over the base.

It doesn't seem like you really need two pumps, but you could add a second and then turn both pumps way down. This will help with heat and can help with noise. You also get the benefit of two pump redundancy so if one pump fails, you have another continuing to move water without any problem.

Bottom line, I would slow the pumps down and add some cooling no matter what you choose. Both are good things regarding DDC heat. There really isn't anything for sure regarding what is required for good pump life, but adding some cooling can't hurt and it also help reduce the amount of heat dumping back into the loop. I've run DDCs full speed on higher restriction loops without any cooling at all for long periods of time, but now I tend to add some sort of heatsink or at least air flow over the base regardless. I also don't run the pumps at full speed all the time which helps a bunch too both for noise and heat.

[Slave1974]

Thanks Martin.
Next question:

I am using the DDC-1t's from Bmaverick with the white PCB's from DIYINHK. These are 18w pumps, no PMW. How do I slow these pumps down? I have not found a definate answer on this.

Do I just plug them into a fan controller? if yes, which one is good for these?

I plan on using a XSPC dual bay dual pump reservoir. When, and if, a company makes a dual heat sink, I will buy one, or try to make my own...

[Martinm210]

I haven't seen the white PCBs yet, so I'm not sure which controller that is. The 18W toshiba controller I reviewed actually has a means to control speed with a variable resistor, no controller necessary.
http://martinsliquidlab.files.wordpress.com/2011/04/diyinhk-7c.jpg?w=614&h=850

Alternatively I'm sure one of Koolance's pump speed controllers would work by feeding the pump lower voltage.
http://martinsliquidlab.files.wordpress.com/2011/03/ctr-spd10-1.jpg?w=614&h=451

or a higher end fan controller capable of really high loads.

[Slave1974]

I see a few fan controllers capable of 30+ watts per channel, or do you mean like 50watts per channel?

[Martinm210]

I just don't trust ratings unless they have been tested. I think many ratings are watts at 12V, but heat really doesn't become an issue until you start undervolting to 8V, etc. I know the Koolance SPD10 handles pumps fine, and the Aquaero 5 does fine with heatsink and/or waterblock, but my sunbeam rheosmart while rated at 30 watts couldn't handle a DDC pump under PWM control and even under manual controls gets pretty hot.

Undervolting a pump with a fan controller via analog methods requires dissipating quite a bit of heat. Unless a fan controller has some really large heatsinks or uses some other method like PWM or a transformer, I have my doubts its a good solution for pump control. The Koolance SPD10 uses a transformer to do the work, and the Aquaero has a good sized heatsink and waterblock option.

I think the Alphacool heatmaster also has a waterblock that would probably handle pumps well.

[Kayin]

White PCBs are still Toshiba drivers. I have one here, and a second PCB besides.

[mav2000]

Heatmaster does not have a water block but can easily undercoat a pump. I run From 2600 to 4200 rpm on an automatic control with no issues