Alphacool ST30 vs XT45

[BenTan]

Hi, I'm currently planning my first water cooled build and am trying to decide which radiators to go with. 

 

I'll be doing the build in an Obsidian 750D case with a top 360 rad and a front 280 rad. I'm also going for a quiet build with fans spinning at low RPM. I'll be cooling a gtx 980 Ti and an i7 3770K.

 

From  what I've managed to gather, thinner rads tend to have a lower FPI which means they work better with lower RPMs. So if I'm going for a silent build, should I get the ST30 instead? Or should I go for the thicker XT45?

 

If I want my fans to spin at low rpm say 500rpm or so, would two radiators be enough to make up for dissipation to allow for low RPM?

 

On a side note, I was wondering what would be the best way to power multiple fans at a fixed low RPM?

 

Any help is appreciated.

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Yes that is enough rad space, go with the ST30. Y Splitter.

[W-L]

-SNIP-

 

The FPI on rads is dependent specifically on that certain rad and size, noting that the UT60 has around 8-10 FPI and XT45 10-12FPI both have around FPI while the ST30 about 14-15 FPI. Mainly the reason being the thinner rads have lower cooling potential so adding more fins increases it's surface area but for thick rads that makes it difficult to push air through it.

 

I would suggest going for the XT45 which is a good balanced radiator for lower speed operations and extra thickness, but the ST30 is also good at that FPI.

 

For powering the fans if they are PWM a PWM fan splitter is a good choice ( or 3 pin fan splitter for 3 pin fans):

http://www.swiftech.com/8-WayPWMsplitter.aspx

[BenTan]

The FPI on rads is dependent specifically on that certain rad and size, noting that the UT60 has around 8-10 FPI and XT45 10-12FPI both have around FPI while the ST30 about 14-15 FPI. Mainly the reason being the thinner rads have lower cooling potential so adding more fins increases it's surface area but for thick rads that makes it difficult to push air through it.

 

I would suggest going for the XT45 which is a good balanced radiator for lower speed operations and extra thickness, but the ST30 is also good at that FPI.

 

For powering the fans if they are PWM a PWM fan splitter is a good choice ( or 3 pin fan splitter for 3 pin fans):

http://www.swiftech.com/8-WayPWMsplitter.aspx

I see, i think I'm leaning more toward the XT45 now. About fan control, if I connect the fan splitter to the power supply and leave it disconnected from the motherboard, will the fans still be at full speed?

[W-L]

I see, i think I'm leaning more toward the XT45 now. About fan control, if I connect the fan splitter to the power supply and leave it disconnected from the motherboard, will the fans still be at full speed?

 

Yes the swiftech one will runs at full 12V if the header isn't connected and unfortunately you can only control PWM fans on that one, if you need 3 pin splitter the NZXT grid is pretty good.