ROG Thor PSU with 3090, airflow issue

[TurquoiseA]

Hello, I am building a new PC and I have some thermal questions regarding ROG Thor PSU and a Strix 3090. So as far as I know, in order to properly position the LCD screen on Thor, the fan would need to face upwards, while the fans on GPU normally would face down if directly attached on the MOBO. My question is

1. Would this cause any internal airflow issue?
2. If so, would put the GPU vertically help at all? 
3. If I put the GPU vertically, is there any notable difference between pcie3.0 and 4.0 riser cable? I will be using this PC mostly for machine learning and gaming.

The new PC case would be Corsair 7000D and I am currently eying the MSI Z690 Edge ddr4 MOBO. Thanks!

[SimplyChunk]

the 7000D is tall enough for it to not really affect anything.  if you're in the 2nd and 3rd slot on the case with your card there should be enough of a gap.  Just make sure you got one of the front fans facing that area between the two components to feed the slight vacuum that'll be created there

[TurquoiseA]

3 minutes ago, SimplyChunk said:

the 7000D is tall enough for it to not really affect anything.  if you're in the 2nd and 3rd slot on the case with your card there should be enough of a gap.  Just make sure you got one of the front fans facing that area between the two components to feed the slight vacuum that'll be created there

Thank you for the suggestion. The card is actually going to be put on the first slot. I am not crazy about aesthetic so I guess I won't be needing a riser cable.

 

For the front fans, I am considering 4 x Noctua F12 iPPC 3000RPM 120mm or 3 x 140mm. Do you think that would be too loud? 

[SimplyChunk]

not got a clue, never used those fans.  I'll leave that bit to other's on here

[jones177]

Would this cause any internal airflow issue?

Yes. 

It may be less of an issue with a tower but it was an issue with my 5000D.

My two gaming computers that use 3080 tis are in cases that the PSU is relocated to the side for maximum airflow to the GPU. 

 

The PSU shroud on my 5000d is not removeable. It may be the same with the 7000D.

I also had to add 3 fans on the side when the case had a 3080 ti in it. Bring the total up to 10 120mm fans. 

 

If so, would put the GPU vertically help at all?

No. 

You are trading one problem with another. 

 

If I put the GPU vertically, is there any notable difference between pcie3.0 and 4.0 riser cable? I will be using this PC mostly for machine learning and gaming.

No. 

Run benches in a slot first so you can spot any performance issues. 

 

My 3090 is in a CM H500M with the stock fans. It is the only case that I could do this with a high end 30 series card. The rest of my cases had to be modified or replaced.

 

5 minutes ago, TurquoiseA said:

For the front fans, I am considering 4 x Noctua F12 iPPC 3000RPM 120mm or 3 x 140mm. Do you think that would be too loud? 

For intake fans I use Noctua NF-A12x25s.

 

120mm fans are loud. 140mm fans are less. I usually use cases with 200mm fans with a big Noctua air coolers for my productivity builds. I can't hear the i9 9900k/3080 ti computer that is on the table 3ft away from me that use this setup but I can hear the 5900x/3080 ti computer that uses 120mms that is about 8ft away from me.