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I am currently using a modified v3. When it kicks in, the PSU fan is currently the loudest part of my printer by a long shot. This is why I am wondering what the arguments pro/con to converting to an ATX style PSU. I have a couple efficient and quiet PSU's laying around. If I understand correct the Duet that I use even supports communicating with the ATX style PSU's.

And insights are much appreciated.

My opinion would be that it would be easier to change the fan in the existing power supply.

The disadvantages of ATX PSUs are that you generally need to put a dummy load on the 5V output, the output voltage is not adjustable, it is likely to be a little less than 12V, and unless you buy a good brand name PSU then it is likely to be not well regulated. All of which means that you may be short of bed heating power, unless you currently have a surplus.

The advantage is that you can set up the firmware to turn off the 12V power at the end of a print.

Thanks for the insights.

Mac The Knife wrote:My opinion would be that it would be easier to change the fan in the existing power supply.

I might look into replacing the PSU fan. The problem with doing that is knowing if you still got enough cooling going on. Since the PSU doesn't have any temp readout's there is no way of knowing this.

dc42 wrote:The disadvantages of ATX PSUs are that you generally need to put a dummy load on the 5V output, the output voltage is not adjustable, it is likely to be a little less than 12V, and unless you buy a good brand name PSU then it is likely to be not well regulated. All of which means that you may be short of bed heating power, unless you currently have a surplus.

The advantage is that you can set up the firmware to turn off the 12V power at the end of a print.

I have a spare Corsair RM650i laying around so the good brand name part would be covered

I would never use an ATX power supply. I don't think they are very suited to the quickly changing power demands of PWM. ATX has only one advantage:

dc42 wrote:The advantage is that you can set up the firmware to turn off the 12V power at the end of a print.

And that is nicely covered by a good industrial PSU plus this:
http://doc.3dmodularsystems.com/ps_on-kit-assembly/

The V3 isn't designed to use an ATX power supply - it simply won't fit. You'd be better off getting a Noctua (or similar) fan to replace the fan in the 29A power supply the v3 has.

g.

Nxt-1 wrote:Thanks for the insights.

Mac The Knife wrote:My opinion would be that it would be easier to change the fan in the existing power supply.

I might look into replacing the PSU fan. The problem with doing that is knowing if you still got enough cooling going on. Since the PSU doesn't have any temp readout's there is no way of knowing this.

dc42 wrote:The disadvantages of ATX PSUs are that you generally need to put a dummy load on the 5V output, the output voltage is not adjustable, it is likely to be a little less than 12V, and unless you buy a good brand name PSU then it is likely to be not well regulated. All of which means that you may be short of bed heating power, unless you currently have a surplus.

The advantage is that you can set up the firmware to turn off the 12V power at the end of a print.

I have a spare Corsair RM650i laying around so the good brand name part would be covered

The easiest way to make sure you have sufficient cooling is to look up the fan that is in the unit, and find a fan with a similar CFM profile. Likely the Noctua in the same size is better. Also, an RM family PSU is one of the worst choices from corsair, as it will attempt to run the fan at zero throttle until it hits either a load threshold, or is near thermal overload. I had a Corsair CX750 in mine for a while, and that eventually popped something internally which blew the fuse. I now use an AX760 in my V2, with the fan in active mode rather than semi-passive. I also have a meanwell 24V external supply, and that isn't too bad noise-wise. The hotend fan is definitely louder.