That flow is awfully slow.  I jut converted 12 LPM and it comes out to 3.17 GPM.  That's slow and will effect your temps while your water coolant temps look good.  You need to be in the 0.8-1.5 GPM range at best for an efficient running loop to utilize your rads properly while having decent air flow going through them via ambient cool air and having the rear as exhaust.
 
(No Ahomes, we're not going intake in the rear.    Maybe you like it that way but we don't. )
 

AHowes
I've had prob 8 beers and a key lime pie and feel fine tonight and I wana barf after looking at that.

Please do a cross pattern with the goop on the next try.

TiN_EE
I've tested HC block last week, and got temp difference ~8c idle to load (32 -> 40c) in TimeSpy. Loop was with EK XE 360, 3 fans (same ones used on Hybrid coolers). 

What was your baseline temps for the OE AIO?  Do you think the EK DDC3.1 on the older EK predator 360 will flow enough for the HC block?    

HawkOculus

GTXJackBauer
That flow is awfully slow.  I jut converted 12 LPM and it comes out to 3.17 GPM.  That's slow and will effect your temps while your water coolant temps look good.  You need to be in the 0.8-1.5 GPM range at best for an efficient running loop to utilize your rads properly while having decent air flow going through them via ambient cool air and having the rear as exhaust.
 
(No Ahomes, we're not going intake in the rear.    Maybe you like it that way but we don't. )
 

AHowes
I've had prob 8 beers and a key lime pie and feel fine tonight and I wana barf after looking at that.

Please do a cross pattern with the goop on the next try.

3 GPM vs. 1.5 is higher though so I guess I’m unaware of something?

Yeah I caught that as well. Hehe

As others have said - your Hydronaught is borked. Most likely the tube was left open for too long. I've had the same problem with that stuff and I go through a lot of it. It only takes an hour or two for it to dry out.

So you payed $299.99 ontop of an AIO card for $1889.99 which already does great and you're getting worse results than it? I would be pissed lol.

Nah, it needs quality fans. It will run 40-45*c under load on decent Noctua's.

So after reading through most of these it seems most think it's the paste. It was a brand new tube, and those aren't cracks, and it's not that dark. I just didnt use the flash in my camera, the paste has ridges where I pulled up on the block and it pulled off. I guess I'll use a different paste this afternoon after work and try again.
In regards to the pattern, I actually spread it evenly over that card. Sorry that makes you sick? I'll keep you in mind next time I apply thermal paste.
As for the flow, I'm pretty confused as to why 3 GPM is slow but I need to be in the 0.8-1.5 which seems slower.
I have an EK 360 slim and 420 Slim with corsair 120/140 pros in push pull on both. So I dont think it's the fans. And yes after spending this much on a card and then a block for it and now getting worse temps I am pretty sad, especially since my block came with a screw broken from the acrylic.
I have a protection plan on the pump and I can replace it with a new one. Is. D5 enough for a HC, mono block and 2 rads?
Thanks for the helpful comments!

Jahusaphet
So after reading through most of these it seems most think it's the paste. It was a brand new tube, and those aren't cracks, and it's not that dark. I just didnt use the flash in my camera, the paste has ridges where I pulled up on the block and it pulled off. I guess I'll use a different paste this afternoon after work and try again.
In regards to the pattern, I actually spread it evenly over that card. Sorry that makes you sick? I'll keep you in mind next time I apply thermal paste.
As for the flow, I'm pretty confused as to why 3 GPM is slow but I need to be in the 0.8-1.5 which seems slower.
I have an EK 360 slim and 420 Slim with corsair 120/140 pros in push pull on both. So I dont think it's the fans. And yes after spending this much on a card and then a block for it and now getting worse temps I am pretty sad, especially since my block came with a screw broken from the acrylic.
I have a protection plan on the pump and I can replace it with a new one. Is. D5 enough for a HC, mono block and 2 rads?
Thanks for the helpful comments!

You should've got HWLabs and not wasted your money on EK.

I would also say it’s the paste. I understand that it might have been new tube but really something is causing it to be higher. The thermal pad would be the only thing I could think of for it.

I always use the 5 dots pattern like on a domino and always use the coolermaster  mastergel-maker  
                                             

Jahusaphet
 
As for the flow, I'm pretty confused as to why 3 GPM is slow but I need to be in the 0.8-1.5 which seems slower.  I have an EK 360 slim and 420 Slim with corsair 120/140 pros in push pull on both. So I dont think it's the fans. And yes after spending this much on a card and then a block for it and now getting worse temps I am pretty sad, especially since my block came with a screw broken from the acrylic.
I have a protection plan on the pump and I can replace it with a new one. Is. D5 enough for a HC, mono block and 2 rads?

Please reread my responses.  I never said actually 3.0 GPM is slow (error converting 12 LPM to GPM on my end) but don't believe that is accurate either unless you're using a more powerful industrial pump.  You do not have 3.0 GPM running in your loop because you'd have so much pressure build up and bubbles up the wazoo and ......ok it's not realistic.  I know this because I own two D5s myself.  You'd be the first person in my almost 10 years into custom cooling with such a flow I've ever heard of.  You're not even bothered by the numbers you're telling me which tells me you never read intro to custom liquid cooling to get a sense of the basics and where things are at but hey, many people do the same so to each their own. 
 
You have temp issues with '3.0 GPM'.  I'd say lets start over on the troubleshooting and as helpful everyone is, I feel everyone has a difference sense of direction on how to go about this.  I say, get your basic custom cooling numbers right first and go from there so you're singling out and moving on to the next step.

GTXJackBauer

Jahusaphet
 
As for the flow, I'm pretty confused as to why 3 GPM is slow but I need to be in the 0.8-1.5 which seems slower.  I have an EK 360 slim and 420 Slim with corsair 120/140 pros in push pull on both. So I dont think it's the fans. And yes after spending this much on a card and then a block for it and now getting worse temps I am pretty sad, especially since my block came with a screw broken from the acrylic.
I have a protection plan on the pump and I can replace it with a new one. Is. D5 enough for a HC, mono block and 2 rads?

Please reread my responses.  I never said actually 3.0 GPM is slow (error converting 12 LPM to GPM on my end) but don't believe that is accurate either unless you're using a more powerful industrial pump.  You do not have 3.0 GPM running in your loop because you'd have so much pressure build up and bubbles up the wazoo and ......ok it's not realistic.  I know this because I own two D5s myself.  You'd be the first person in my almost 10 years into custom cooling with such a flow I've ever heard of.  You're not even bothered by the numbers you're telling me which tells me you never read intro to custom liquid cooling to get a sense of the basics and where things are at but hey, many people do the same so to each their own. 
 
You have temp issues with '3.0 GPM'.  I'd say lets start over on the troubleshooting and as helpful everyone is, I feel everyone has a difference sense of direction on how to go about this.  I say, get your basic custom cooling numbers right first and go from there so you're singling out and moving on to the next step.

If you have a link to the intro to custom cooling that'd would be helpful, I have read and watched plenty of things and have been running custom loops for 2 years. I'm not a veteran but not a full blown newb.
I havent exactly looked up what my waterflow should be at normally and I was just giving the answer my flow meter indicated. As for re-reading your response. I want the only one confused, I read it many times. As far as the pump speed goes its 720LPH which is close to half of the 1500LPH stated on the spec sheet. So im losing half of the flow through the loop?
If you want to help please help, but just saying im obviously a noob and need to just start over isnt helpful. I'm not looking for why I'm wrong, I'm looking for help.

Slim line EK rads are not going to give great or even good results, IMO. As others have said, redo the TIM, put the card into a single loop, try a new flow meter, and swap rads for best performance. The straightest line of flow is your best bet. Use 45* vs 90* elbows or no elbows and soft 1/2 tubing if you can. The TIM looks thick and old or dunked in water or something. Looks like it never was able to spread or thin out.

TiN_EE
I've tested HC block last week, and got temp difference ~8c idle to load (32 -> 40c) in TimeSpy. Loop was with EK XE 360, 3 fans (same ones used on Hybrid coolers). 

What was the water temperature and ambient with both setups before testing? How about after and hr or two of testing? What temps were the design team seeing during testings?

Zeddivile
I think the HC KPE is going to need its own loop to match the perf of the stock CLC. When my replacement HC arrives I can though it in its own loop Nemesis 360GTX and the same EKD5 pump and see what the performance looks like.
 
It's nice to hear TIN's take aka ~8c difference idle to load but am still unsure sounds like fake news... Over a couple hours of looped timespy stress testing the liquid temp should have climbed at least 2c. So was that just a quick test or what are we even talking about with the so called 8c difference. difference over liquid temp?
 
While we are at it what is the difference in cooling performance on the VRM and MEM vs CLC?
 
@dwexpress

I use kryonaut to draw the profile of Der8auer's face on my GPU dies and CPU IHS's.  It takes a while but heh its worth it. Also sometimes the outline of a unicorn or a warlock.