The back is a bit weird

@DildorTheDecent The back suggests that you can put an ITX mobo in horizontally, just like with the Cooler Master 110, 130 and others.  Why I would actually want to do that in such a big case is a completely separate issue...maybe extra space for water cooling and/or drives???  I would say that showing off your GPU lights would be a reason, but that side panel would choke its airflow like nobody's business...

The vertical slots are for a vertical GPU. Pretty much every new case with glass these days will also have a vertical GPU slot. 

There's no rear fan hole. That's the kicker.

although it wouldn't make sense the top portion with the grill should be able to let off some heat.  but since it's steel , i'm afraid the case could get a bit toasty if you manage to place your hand on top of it.

Heat rises fam. Since the top cover comes off that'll help a bit too. 

but still it will trap it since there's no exhaust out back it would all funnel out from up there. that constant contact with with hot air would probably make it one the toastiest case top. compared to the ones with.

don't know how exact scenario it would be,  it might be cooler since the airflow pressure would be focused & strong , it could exhaust out more quicker & efficiently rather than diffused flow which is weak from an opened up mesh grill design .

There is 200mm fans top and bottom. 

The heat won't be an issue. 

Plus nobody buys this case for performance. It's all about looking pretty. 

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Plus nobody buys this case for performance. It's all about looking pretty

Damn right! The forbidden Truth..

This case actually has the best GPU temps since the dual 200mm fans blow right into the gpu. But as a result the CPU Air cooler actually gets shafted for airflow. Ironically using the rotatable PCI-E slots to make the GPU vertical helps  

https://www.gamersnexus.net/hwreviews/3384-cooler-master-sl-600m-review-thermals-build-quality-noise