pastrychef's Asus ROG Strix Z370-G Gaming (WI-FI AC) build w/ i9-9900K + AMD 6600 XT

[pastrychef]

As this build has reached a state of nirvana (honestly, I can't imagine a hackintosh running macOS any better than this), I got a bit bored... I wanted to see how a video card with an "open" style cooler would affect the system. So, I procured a Power Color Vega 56 Red Dragon to do some testing.

The Red Dragon that I got has been flashed with a Sapphire Vega 64 Nitro+ BIOS. I did a quick Unigine Heaven run before swapping out my Vega 56 with reference style "blower" cooler. Once the Red Dragon was in, I ran Heaven again. With the blower cooler, my CPU temps never exceeded 37C. With the open cooler, my CPU temps were at 50C!! That's a huge increase. Unfortunately, I don't know of any way to see VRM and/or RAM temps in macOS, but I would imagine that their temps would also see significant increases.

Fidgeting with undervolting the Red Dragon did nothing to help the temps of the CPU or the Red Dragon itself. In fact, I found that running the Red Dragon with the stock macOS 10.14.5 power table yielded the best benchmark results. However, those results were still lower than my tweaked Vega 56. In Heaven my tweaked Vega 56 gets ~72.5fps vs ~68.5 with the Red Dragon running a Vega 64 BIOS. On the other hand, the Red Dragon was completely inaudible to me and GPU temps never exceeded 65C. With the blower, I can hear the movement of air and GPU temps got as high as 72C.

So, what's the takeaway here? Well, if you overclock your CPU and are using an air cooler, you should probably stick with video cards that use blower style coolers. The heat from a video card with an open style cooler will keep heat inside your case rather than push it out of the case. The amount of heat can be significant depending on the video card. I don't know how much impact this would have if you are using water cooling, but I would guess that VRM and RAM would get even hotter since there will be less air circulation around them without the fans of an air cooler.

Just something to consider for those who are thinking about a Radeon VII which only comes with a open style cooler...

 

[scottkendall]

As this build has reached a state of nirvana (honestly, I can't imagine a hackintosh running macOS any better than this), I got a bit bored... I wanted to see how a video card with an "open" style cooler would affect the system. So, I procured a Power Color Vega 56 Red Dragon to do some testing.

The Red Dragon that I got has been flashed with a Sapphire Vega 64 Nitro+ BIOS. I did a quick Unigine Heaven run before swapping out my Vega 56 with reference style "blower" cooler. Once the Red Dragon was in, I ran Heaven again. With the blower cooler, my CPU temps never exceeded 37C. With the open cooler, my CPU temps were at 50C!! That's a huge increase. Unfortunately, I don't know of any way to see VRM and/or RAM temps in macOS, but I would imagine that their temps would also see significant increases.

Fidgeting with undervolting the Red Dragon did nothing to help the temps of the CPU or the Red Dragon itself. In fact, I found that running the Red Dragon with the stock macOS 10.14.5 power table yielded the best benchmark results. However, those results were still lower than my tweaked Vega 56. In heaven my tweaked Vega 56 gets ~72.5fps vs ~68.5 with the Red Dragon running a Vega 64 BIOS. On the other hand, the Red Dragon was completely inaudible to me and GPU temps never exceeded 65C. With the blower, I can hear the movement of air and GPU temps got as high as 72C.

So, what's the takeaway here? Well, if you overclock your CPU and are using an air cooler, you should probably stick with video cards that use blower style coolers. The heat from a video card with an open style cooler will keep heat inside your case rather than push it out of the case. The amount of heat can be significant depending on the video card. I don't know how much impact this would have if you are using water cooling, but I would guess that VRM and RAM would get even hotter since there will be less air circulation around them without the fans of an air cooler.

Just something to consider for those who are thinking about a Radeon VII which only comes with a open style cooler...

How many Case Fans do you have? This could be a big factor. Also I would guess that water cooling would help in this scenario since the cooling happens at the front of the case before the GPU. I seem to remember watching a video and the overall system temp to be lower with the open shroud and water cooling then when they used the Blower style with Water Cooler.

 

[pastrychef]

How many Case Fans do you have? This could be a big factor. Also I would guess that water cooling would help in this scenario since the cooling happens at the front of the case before the GPU. I seem to remember watching a video and the overall system temp to be lower with the open shroud and water cooling then when they used the Blower style with Water Cooler.

Here's a picture I found from googling. My setup is pretty much exactly the same minus one video card. As you can see, under the drive bays, there are two fans. Both are 120mm Noctuas and I also have a single 120mm Noctua in the rear for exhaust.


The cooling on this case is fantastic. There's really no obstructions to airflow. Also, the fan that's in the middle of the Noctua heatsink sits low enough that it should offer at least some air circulation over the rear VRM heatsink.

 

[scottkendall]

The cooling on this case is fantastic. There's really no obstructions to airflow. Also, the fan that's in the middle of the Noctua heatsink sits low enough that it should offer at least some air circulation over the rear VRM heatsink.

Maybe you just need more air out to make up for the open set up. I really like that my PSU is on the bottom takes air from the bottom outside and spits it out the back. That case looks very small, maybe not the best choice for an open shroud.

 

[pastrychef]

Maybe you just need more air out to make up for the open set up. I really like that my PSU is on the bottom takes air from the bottom outside and spits it out the back. That case looks very small, maybe not the best choice for an open shroud.

I don't know how to force even more air in to the case. Lol. I suppose I can replace the two front fans with Noctua NF-A12x25s...

I liked the size of the case and the fact that the overall layout is very reminiscent of my old Mac Pro. There's enough room for:
3x 3.5" hard drives
3x 2.5" hard drives
Noctua NH-D15S (160mm height)
Enough room for video cards that are 14.5" long

The fan on my power supply doesn't turn on until there's at least 50% load. It's an 850W power supply and I don't think the fan has ever been on... I like that the heat from the power supply can exhaust out the top of the case.

 

[scottkendall]

I don't know how to force even more air in to the case. Lol. I suppose I can replace the two front fans with Noctua NF-A12x25s...

I liked the size of the case and the fact that the overall layout is very reminiscent of my old Mac Pro. There's enough room for:
3x 3.5" hard drives
3x 2.5" hard drives
Noctua NH-D15S (160mm height)
Enough room for video cards that are 14.5" long

The fan on my power supply doesn't turn on until there's at least 50% load. It's an 850W power supply and I don't think the fan has ever been on... I like that the heat from the power supply can exhaust out the top of the case.

Those two drive bays at the top front are taking up a lot of space lol

 

[pastrychef]

Those two drive bays at the top front are taking up a lot of space lol

I use those for my 3x 3.5" drives. They are in hot swap cages.

 

[aussiepilot]

I don't know how to force even more air in to the case. Lol. I suppose I can replace the two front fans with Noctua NF-A12x25s...

I liked the size of the case and the fact that the overall layout is very reminiscent of my old Mac Pro. There's enough room for:
3x 3.5" hard drives
3x 2.5" hard drives
Noctua NH-D15S (160mm height)
Enough room for video cards that are 14.5" long

The fan on my power supply doesn't turn on until there's at least 50% load. It's an 850W power supply and I don't think the fan has ever been on... I like that the heat from the power supply can exhaust out the top of the case.

Looking at that case, I suspect that a negative pressure setup would work better for the open cooled GPU, particularly because if means reversing the airflow from back to front.

Without any case fans at all, the air from the GPU (and CPU) would rise to the top of the case (between the PSU and disks), and as it cooled, it would spill over the top and fall behind (under) the MB. You would end up with internal airflow rising in the big part of the case and falling in the small gap under the MB - especially if the GPU and CPU fans were stopped.

With your current positive pressure setup, the cool air from the front will be split. Most will be directed through the CPU cooler and exhausted through the back, but a significant amount will pick up the hot air from the GPU and blow it round the case, probably following the natural air flow path, so you end up heating the MB from below and then have hot air mixing with the air going through the CPU cooler - bad all round.

That natural motion will happen whenever a fan can't prevent it. In your case, most air from the GPU will rise in that area. The exhaust fan will only deal with the air from the CPU cooler and the front case fans, which means the GPU heated air will be forced back into the general airflow in a position where it will come through the CPU cooler. On the way, it will be heating the MB.

If you reverse the case fans, the CPU gets pure external air, so should have the best temps possible. The GPU heated are will be drawn to the front of the case, and even if it spills over the top, that air will also be drawn to the front before it can heat anything else.

With the closed blower cooler, you have no GPU heat remaining in the top of the case, so the air moving round the case helps cool the disks and MB instead of heating them, resulting in good cooling all round. Because the GPU air is being exhausted at the back, you want your current front to back airflow to prevent the GPU air being sucked back in again.

 

[nib01]

What is the equivalent full size ATX Intel motherboard for this build?

 

[scottkendall]

What is the equivalent full size ATX Intel motherboard for this build?

I use a z370-F Gaming; there is also an z370-I, z370-H Gaming though none of them have a built in wifi. The z370-E has wifi so it might be the closest to the z370-G.