Mac Pro replica (late 2013) - low power design

[JuanLobo]

Hmm,and what about this: A fan located under the base, lets say in the 3D print or in the adjusted wooden legs. They do also slim versions of the 12cm, this should not be disturbing too much. Than a motherboard sitting on the bottom part with a PSU on the top. The PSU would blow the air into the solid top part (ideally made out of aluminum), located just few millimeters from the PSU, the air would than go to the sides and leave the case with the main airflow.
Just an idea.

BTW do you guys really need traditional PSU? How many Watts do you really need? Because there are PicoPSUs up to 200W. The power brick might be a problem thought.

Edit: //
Dschijn never mind the second suggestion, I just saw your rig in description and 200W must sound like and insult to you

If you go with a 3D printed base, you gain about 30mm of height to put stuff in. As long as you don't put a GPU behind the logic board, then you can stack the PSU/Fan/motherboard very closely together, and have space at the top for the cool vent. The problem with adding a GPU is you need almost 15-20mm at the top of the GPU for the right angle cable, and another 10mm at the bottom to give the card a little breathing room to get rid of the heat at that end.

For a no-GPU, internal PSU setup, I would have the PSU at the base, then the fan, then the logic board. You wouldn't want the fan at the top because it would be blowing into a flat plate. You wouldn't want the fan at the bottom because it would just be blowing into the solid base of the PSU. Any space left over in that design, I would put toward space between the PSU and fan so the fan can pull more air around the PSU. I would go with a 140/150mm round fan that uses 120mm mounting holes, just so you can pull as much air from around the PSU as possible.

If you really want a GPU, and the cool top exhaust, and not have a big hole in the back like Sascha, it might take looking for an AMD ITX length GPU, and possibly soldering an HDMI extension right to the card to save space at the top. (Or going with a high wattage pico PSU and external supply). The nVidia GPU needs breathing room on all sides, an AMD card might not.

 

[klausi13]

Luckily mine is silent at all times - and I am a big pitch noise hater too Hopefully the second one will be fine.
The power consumption is really good!

With my new 90W brick the high pitch noise is finally gone and the idle consumption is now at 18 watts and <25 watt while surfing via wifi

 

[klausi13]

Short update of my low power build. I'm almost finished. Building is complete, windows and mac os running and now i just need to pimp my wifi setup to boost the signal by finding the best spot for the antennas.

The system is nearly unhearable. Now the fan in the cinema display is the loudest sound source on my desk

The power consumption stay between 18-30 watts during normal operation, with peaks up to around 80 watts during high load like gaming.

Some pictures during the last build steps:

 

[JuanLobo]

Short update of my low power build. I'm almost finished. Building is complete, windows and mac os running and now i just need to pimp my wifi setup to boost the signal by finding the best spot for the antennas.

Well done! I am fighting with the antennas too. If I have the antenna right behind the IO plate, I can't connect to my wifi. It gives a "Connection Timeout" when trying to authenticate the password. But, once the password is authenticated, I can put the antenna back near the IO plate. It makes no sense.

I even lined the inside of the bin with heavy aluminum foil tape to try and eliminate RF noise, but it doesn't help. Maybe all the metal parts and the foil shielding need to be tied together with wire so they are all grounded.

 

[Mr.Target]

Klausi13, schön ! It is really neat! I wonder if you need a fan on that CPU cooler, is 45W to much for a passive? And what is your plan with the the top part? Do you want to make the balsa legs all way around to imitate MacPro fan cover? Because if not, you should be able to hold the top part on spot by using a "monopod" attached to the motherboard support, so you cannot see any support on the edges.

About the wifi, I am not the expert at all, but I have noticed antenna under the top part- currently I am messing up with walkie talkies a little bit, and the think is: if you want to communicate with a transmitter (router) that is on the same floor as you are, you should keep the antenna(s) in the vertical direction. If you you want to communicate with the device above or under you, keep them horizontal. This would explain me why JuanLobo was able to connect to his neighbor (btw ) but not to his own router... But again, it is just a thought, I am not sure if it is the same for a wifi and I assume you are trying more positions anyway...

 

[klausi13]

Klausi13, schön ! It is really neat! I wonder if you need a fan on that CPU cooler, is 45W to much for a passive? And what is your plan with the the top part? Do you want to make the balsa legs all way around to imitate MacPro fan cover? Because if not, you should be able to hold the top part on spot by using a "monopod" attached to the motherboard support, so you cannot see any support on the edges.

About the wifi, I am not the expert at all, but I have noticed antenna under the top part- currently I am messing up with walkie talkies a little bit, and the think is: if you want to communicate with a transmitter (router) that is on the same floor as you are, you should keep the antenna(s) in the vertical direction. If you you want to communicate with the device above or under you, keep them horizontal. This would explain me why JuanLobo was able to connect to his neighbor (btw ) but not to his own router... But again, it is just a thought, I am not sure if it is the same for a wifi and I assume you are trying more positions anyway...

Thx For now the top plate will stay like it is. I don't want to attach more legs to imitate the fan cover right now. If i go for your monopad idea i will loose the space under the plate for additional stuff. I'm thinking about building an sd card reader into the top plate.

The CPU fan ist not necesarry but i noticed that without it the base fan spins much faster higher on high load (its connected as CPU cooler fan). With this fan the temperatures stays even on high load very low. Only the base fan will speed up a bit. The fan on the CPU cooler stays constantly at 500 RPM.

For the wifi antenna setup i will try differnt vertical spots to see if the signal gets stronger.

 

[Dschijn]

Good job! Could you go more into detail for the fan speeds and the temperatures? Also maybe a word to the noise.
Which fan are you using on the CPU cooler? The 92x92x14mm Noctua?

 

[klausi13]

My system is now finished. As said before i stick for now with the white color of the bin. It fits nice to my keyboard and mouse and looks nice on the desk. As you can see i've added a little extra to the front of the bin



I'm is still pimping my wifi setup. I've decided to switch my Azureware AW-NB290 for a card with the Atheros 8290 chip. I had a AR8390 pcie card in my last computer and had very good wifi signals with it. I can live with the loss of bluetooth.


To test my cooling i let prim95 work for around 45 minutes:



During the stress test with prim95 the system consumed 77 watts at its peak (normal operation 19-25 watts). The temperature of the CPU goes 20° C up and the 120mm base fan spins up to 800-900 rpm (idle 400-450 rpm). This fan is connected to the CPU fan connector on the mainboard, so it can spin up to 1500 rpm max when the CPU heats up too much and reaches 70° C. When this fan rotates with 1500 rpm a very strong wind flow is coming through the opening on the top.
The second fan (@Dschijn: yes it is a Noctua 92x92x14mm) replaced the fan on the Thermalright cooler because it has a 4pin pwm connector and can so be controlled by the mainboard bios. It is set to fix to 40% pwm, which is around 1100 rpm. Sadly the fan control of the Zotac mainboard only works well when you use 4pin fans. On my last Gigabyte mainboard i could control even 3pin fans with the bios.

The overall noise of the system is very pleasant. It is very quiet during normal operation and its hard to make out any fan noise. You can bearly hear the Noctua fan. If you set this fan to 30% it rotates with 800 rpm and can not be hear anymore but the CPU temperatues will raise 5-8 °C. The base fan is only hearable when it spins up over 1000 rpm and more.

After finishing the build i'm right now tweaking Mac OS to geht the maximum power out of the system. I found something strange in the power settings of the systems and not sure to fix this. In the power setting is no slider to adjust the time when the system goes to sleep:



But the system report says that after 10 miuntes idle the system goes to slep, and so it does. Does anybody know how to enable the slider or how to fix this ?

 

[Dschijn]

That are great results. Imho… I would reduce the fans speed as much as possible to make the system really quiet. As long as the temperature doesn't exceed 70°C you are fine.

 

[klausi13]

That are great results. Imho… I would reduce the fans speed as much as possible to make the system really quiet. As long as the temperature doesn't exceed 70°C you are fine.

Thanks. Over the next weeks i might have the time to play with the fan settings during different load settings (gaming, photoshop, lightroom etc.). For now its already the quietest computer i've ever had, and i have good ears

Any ideas where the slider for the standby in the power settings is gone ?