dreamsensei
So I figured I'd share a bit of my experience with the same issue as to help others who are trying to figure out how to better manage their temps.
 
Quick system stats for any pertinence :
CPU : i9-9900k - 5.0ghz @ 1.30v (AVX offset of 2)
Motherboard : Gigabyte Aorus Ultra Z390
Video Card : EVGA 2080ti FTW3 Ultra Hybrid (Push/Pull as rear exhaust, Corsair ML120 Pro fans, stock fan curve)
RAM : 32 GB of Corsair Vengeance RGB 3200mhz (XMP enabled)
PSU : Seasonic Prime Titanium 850w
Case : NZXT H700
Cooler : Corsair H150i Pro (Front mounted, Push/Pull with Corsair ML120 Pro fans @ static 1600 RPM)
 
I had recently transferred my system from a Cooler Master Masterbox 5 since I wanted to have more cooling options (said case only had 3 120mm intakes and a single 120mm exhaust). I setup the new case with front CPU rad intake, rear GPU rad exhaust, and 3 exhaust fans in the roof to try to expel some of the hotter air. After getting the rig up and running, I noticed that it was icy cold at my exhaust on the top fans, but still warm behind the rear exhaust where the GPU rad was (more on this later), so I didn't really question I had done the right thing as I figured a cold exhaust meant the system was getting excellent cooling overall. Initially I didn't have any of my radiators in Push/Pull as I felt like my ambient temp of 18c in the basement was perfectly acceptable, especially with what most would consider relatively beefy cooling outside of a custom loop. 
 
So I'm playing Yakuza Kiwami 2 the other day, and for s**ts and giggles I go and look at my temps for the video card :
 
GPU : 60
MEM2 : 68
MEM3 : 70
 
Bleeeccchhh, right? I'm running at stock, it should do better than that! So, I find this thread and take a look at various suggestions. The one that caught my eye said something like "top exhaust? you might be starving your radiator and sucking out the cold air before it reaches it". So, I turn off all the top exhaust fans :
 
GPU : 56
MEM2 : 63
MEM3 : 66
 
When I turned the top exhaust fans back on, the temps went right back to the prior "hot" ones. I tried a variety of settings between 500 RPM and 2400 RPM, and the results would get worse as I revved up the fans higher. So yes, I was starving the exhaust radiator for the video card. Next, I decided to go push/pull on the video card radiator :
 
GPU : 54
MEM2 : 61
MEM3 : 62
 
That helped a bit, but I felt like I was still a bit too hot since others in this thread have said "yadda yadda my temps never go over mid 50s. So I do a little more Googling, and eventually I run across a Jayz2Centz video where the topic was "Does Push/Pull really matter on a radiator". Whereas his test wasn't very scientific and very specific to his setup, he did one test where he show 2 identical fans side by side where one had a 25mm AIO radiator in front of one of the fans. He taped two strips of paper and show how much the fans blew them at different RPMs. Contrary to what so many have said about AIO radiators not really impeding airflow, it cut down the actual airflow from the fan on the radiator by half. When he switched the same radiator to push/pull, it was noticeably better (though still not full strength).
 
My only intake fans are in push in front of my 360 rad. So, because of this, I decided to do push/pull on my 360mm cpu radiator instead of just push. Low and behold :
 
GPU : 50
MEM2 : 55
MEM3 : 57
 
Granted, I'm running the card at stock...but I think the takeaway here is :
 
1. Top exhaust fans ABSOLUTELY can steal cold air from the hybrid radiator if it is mounted in rear exhaust. I would imagine a top exhaust radiator would also interfere with the rear exhaust hybrid radiator.
2. Intake fans across a radiator slow your airflow DRAMATICALLY, and thus lowers their effectiveness as intake...even on dinky AIO rads. If you're front-mounting the CPU rad, consider doing push/pull IF ONLY to increase airflow to the case, let alone cool the rad better.
 
I realize this was a bit long-winded, but I wanted to be very clear and present findings rather than say "Hey, try this" so that anyone struggling with their hybrid could maybe find a solution.

dreamsensei

cyrax2768
 
What did you end up as your final config?  Did you keep push/pull on Video card Rad in the back, and then push/pull on the CPU rad in front, and now with this turn back on your top exhausts?

The top exhausts were stealing the cold air from the GPU rad in the rear no matter what speed I ran them, or configuration. Apparently 1 single exhaust point was more than enough for the system to run well.
 
In fact...after attempting the GPU rad intake rather than exhaust method, I decided to play a little more. I reversed the fans on top that were all exhausting and made them intake. This means I currently have the following :
 
Front Intake - 360 Rad with Push/Pull @ 1500 RPM
Top Intake - 3x120mm fans @ 1500 RPM
Rear Exhaust - EVGA Hybrid Rad with Push/Pull @ Stock fan curve
 
All fans are Corsair ML120 Pro. Ultimately this shaved another 2 degrees off my best temps (again, using Heaven benchmark):
 
GPU : 48/49 (it moved back and forth, so I assume this was more like 48.5)
MEM2 : 53
MEM3 : 54/55 (it moved back and forth, so I assume this was more like 54.5)
 
Not only are my temps stellar now, but my case is MUCH cooler overall - my RAM dropped several degrees, my M.2 dropped dramatically, and all the temperature points are a couple degrees cooler. So yeah, the next time someone says "Don't use the top as intake, HEAT RISES"...try it anyway and see what results you get. Everything is situational, and what works for one won't necessarily work for the other.

dreamsensei
I think the biggest effect on my temps was the top intake fan that's essentially right above the rad. There's so little space between it and the hybrid fan that it's like having the rad as an intake without the side effect of heated exhaust from it blowing into my case.

Islandborn

dreamsensei
The exhaust fans being cool is a sign it's like my setup. Seriously, try as intake.

Dream.... U are a Dream! Your the man dude! Swapped the top 3 fans and my temps went down 5C in Heaven benchmark! Can't believe it! Your'e right! So much for the "heat rises" and people always recommending top fans as exhaust! Just can't believe having only the hybrid cooler as exhaust and all the other fans as intake doesn't cause issues with negative pressure. Other then keeping the side panel off, this seems like the best option. Thanks again!!!

mrosenbu
Well, I'm breaking down and doing a custom loop. 2 x pump/res combos with 2 x 480 rads, one each for the CPU and GPU. Ordered the Kingpin 2080ti and water block. Gets here tomorrow. I'll post pics when it's all done.