Pump choice and flow rate question

Ze-goldfish · February 9, 2015

Hi

This summer I am going to put together my first water cooling loop for my GPU and CPU.

My plan is to make two seperate loops, one for the GPU and one for the CPU, with a Alphacool XT45 360mm radiator, a Alphacool XT45 140mm radiator, 2 QDC4 quick disconnects and a MCP655-PWM-DRIVE pump in each loop.

My problem is, that I want the system to be as quiet as possible while maintaining decent temperatures. Currently I have 8 Noctua fans running at 500 RPM and a H100i pump as my only source of noise, as I have a fanless PSU and only SSD's for storage. The Fans are barely audible from 1 feet away, but the pump is comparably quite noisy at the 2300 RPM.

I was wondering if the MCP655-PWM-DRIVE would be capable of running at lower RPM (more quiet), while still producing enough water flow for specificly my loops.

From graphs on martinsliquidlab.com I have created a flow vs psi graph from which it should be capable of producing about 0.5 GPM at 2000 RPM (40%), but that is still very close to the 2300 RPM of the h100i pump. Would a lower GPM, maybe 0.25-0.3, be enough as I only intent to run one heat generating component in each loop? From what I have read, such low GPM should be enough though at that GPM the temperature difference in the loop would be a few degrees.

Another idea was Swiftechs “new” MCP50X which from this review

http://www.overclock.net/t/1516369/my-review-of-the-swiftech-mcp50x-pump

should be more quiet than the MCP655 at lower GPM.

Which pump would you recommend and would the lower flow rates be sufficient?

Many thanks in advance

Jacob

Enderman · February 9, 2015

if you want quiet, buy a D5 and turn down the RPM

and dont make two separate loops, its a waste of time and money and will give you worse performance and more noise

separate loops are only useful for aesthetics

Ze-goldfish · February 9, 2015

Then we are back at my second question about very low flow rates. Because a single D5 would only be capable of 0.3 GPM at 2000 RPM and i really dont want to run it at much higher RPM than my current pump (h100i) allready does.