The New Watercool MORA IV is MASSIVE

Zarathustra[H]

Extremely [H]
Joined
Oct 29, 2000
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This is maybe a little bit old news now as they launched in July, but I missed it completely, and I figured I cant have been the only one.

So, I have been casually planning a MORA build for some time now, but something else always seemed to get in the way, and I never got around to it.

I had previously seen the old MORA products slowly go out of stock and disappear from the website, and was concerned that they were discontinuing them. But that wasn't the case at all. They were replacing them with a newer, bigger and badder version.

This is the MORA IV Series:

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At first I didn't realize what was going on, other than new aesthetics, and a significant price increase, as their specs page strangely does not mention fan sizes and counts...

But then I realized... All of the units above are pictured with Noctua 200mm fans installed. Which means the middle one is the same size as the old MORA 420 that could take four 200mm fans or nine 140mm fans.

That beast on the right takes NINE 200mm fans or SIXTEEN 140mm fans.

Don't believe me? Here is the 16x 140mm fan frame:

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140mm is now apparently optional, the units ship with the 200mm adapters.

I'd love to go with 200mm fans, as it would make wiring and such much easier, but the static pressure on any 200mm fan I can find is quite frankly pathetic at 1.08 mmH2O.

They list the largest 600 model at 700 x 662 x 75mm or 27.6" x 26.1" x 3.0"

This new thing is beastly, and I love it.

If I ever get around to it, I'll take two, and use them to cool everything in my rack :p
 
I've had a Phobya G-Changer Xtreme NOVA 1080 Radiator 60mm thick with 9-120mm pwm fans combined with dual D5 pumps all external. I use quick connects to my PC. It has seen 3 different builds and a few upgrades in 6 years service. It will easily last another 6 years. However if I was in the market now this would be my go to. The 140's or 200mm fans would be even quiter. For that matter my 9 120s rarly exceed 700 rpm under heavy load (gaming). The MORA has some really nice addons that look sweet too. If you never want to worry about cooling something this is the way to go.
 
I've debated getting a Mora for years. The new ones are crazy.

I wonder how good the passive cooling would be on the large 70cm one if it was mounted horizontal.
 
I've debated getting a Mora for years. The new ones are crazy.

My thoughts exactly.

I wonder how good the passive cooling would be on the large 70cm one if it was mounted horizontal.

Good question.

I remember doing leak testing with my current system (2x480mm + 1x420mm) and even with the system turned off, they got warm to the touch over time from just the heat the D5 pumps (3 of them) dumped into the system over time.

But in this loop, only the 420 was horizontal at the top of the case. The two 480's are vertical in the front.

I'm not suggesting the above is terribly relevant, as it is just slightly less than half of the swept area (~48%) of the new large MORA, and only about a third of it was horizontal. It's just the only data point I have.

Instead of doing that, I'd be inclined to just use the 9x 200mm configuration, and run the 200mm fan at minimum fan speed. I have one of the NF-A20 PWM's (Chromax black, but they have the same specs as the ugly beige/brown ones, at least in 200mm) in my testbench system and I can't really hear it at all at idle.

Though as I am typing this, I can't remember if I used the included noise reduction adapter to slow it down even further or not though)

The official noise spec is 18.1 dba, so even at full speed they are pretty damn quiet, but I guess that is what you get when you take a large fan and run it at only 800rpm (max, 350rpm min)

But what experience has taught me is that even the tiniest bit of forced air can make a huge difference, and if you turn things down enough, you may not hear it at all.

I understand desiring silence (I do as well) but it would seem like wasted potential to go all absolutist and insist on no fans at all. (Besides, you'd probably hear the pump hum anyway)


Personally I gave up on silent water cooling a while back. I just moved my computer to another room, and use long USB and video extension cables instead. Now I can crank the fans and never hear them either way :p
 
Unfortunately, while the MORA's appear to be great, not enough people buy them (because they are expensive and extreme) so there are very few detailed tests out there.

I would - for instance - like to like to know how dense their fins are. My goal would be to learn to what extent the 1.08mmH20 static pressure of the 200mm Noctua NF-A20 series is sufficient to make the most out of them, or if they benefit a lot from using more, smaller 140mm fans many of which have much greater static pressure.

This has been surprisingly difficult to find information.

I mean, you can try to look at the fin density in pictures, but it is so tough to tell, especially since the fact that these are actually 200mm fan slots, not 140mm ones, which throws off the whole perspective, and that I can't seem to find any higher resolution pictures than this:

1725663811767.png
 
Amusingly enough th emost high res imagery I can find is in their launch video on youtube, which is available in 4k:


View: https://www.youtube.com/watch?v=_zcpqSfRXNE

But this appears to be a render. Who knows how accurately the fins are actually rendered.

I tried stepping through it frame by frame, but the only sectiion where the fins are not covered up, and there is something else in frame I can get a size reference on (so I could count them and get an FPI number) the whole frame is zooming, and the motion artefacting in YouTube's 4k bitrates ruins everything. :/


One thing that I learned from this video that is really cool though is this:

1725664081980.png


Having built a system with large numbers of fans, I can tell you first hand how difficult it becomes to manage all the fan cables. Having the fan management built in like this is HUGE.


There are 22 fans connected to the radiators in this pic:

1725664373164.png


It is WAY too easy to accidentally pull on one of the wires and disconnect a fan splitter, and then you spend the next hour trying to squeeze your man hands into tiny places they werent designed to go, to get that one fan connected back in again.

Like this:

1725664536280.png


Seeing this picture almost 5 years later still makes me annoyed.

So yeah, those built in fan headers are huge deal.
 
Amusingly enough th emost high res imagery I can find is in their launch video on youtube, which is available in 4k:


View: https://www.youtube.com/watch?v=_zcpqSfRXNE


Actually, I was so busy looking at the details of the actual product in the video, that I missed a detail in the text.

It doesn't give us much detail, but it does say that the find are "optimized for Noctua 200mm" which must mean they are pretty low density.
 
Looks pretty thicc. Going by the depth of the shroud, about two noctua 200mm fans thick, or about 60mm. Or 90 (95?) mm with the fans+shroud.

I really like the idea of the mora, just could never convince myself to pull the trigger.
 
Actually, I was so busy looking at the details of the actual product in the video, that I missed a detail in the text.

It doesn't give us much detail, but it does say that the find are "optimized for Noctua 200mm" which must mean they are pretty low density.
I think of more concern with Rads like this is flow rates. There is a mile of pipe here. My guess is it looks to be a four-time parallel layout (typical MORA) through 80 tubes or approx. 33 meters (not mm) of pipe running through the 200mm fan optimized MO-RA IV 400 fins. In terms of head pressure, I'd be most interested in seeing a dual DDC vs D5 flow rate comparison in series and parallel. One thing I have learned using large radiator is flow rate is more important than static pressure. In other words, I've never had to worry about going push pull fans to get desired performance. That wasn’t the case with monsta rads for example push pull was a definite plus. I use Air Series SP120 PWM fans. They max out at 2300 RPM. All fans are set in bios with PWM curve. When gaming they rarely exceed 700 rpm and with 100% load stress testing ramp up to 1100 avg or 1200 max rpm. I guess my point is I attribute the performance to the dual D5 pumps not how well my fans push air through the rad. However, the MORA (four-time parallel layout) is a totally different rad config than my Nova which is actually 3-360 rads in series. There may be a good reason why the MO-RA IV 400 addon is a dual D5 pump setup which look awesome btw. Bottom line sweating the details with such a large rad is superfluous.

My setup custom built cart sits below and behind lift desk.
S3Lf1J.jpg

MO-RA IV 400 w/dual D5 + Res
2oCH3e.png
 
Actually, I was so busy looking at the details of the actual product in the video, that I missed a detail in the text.

It doesn't give us much detail, but it does say that the find are "optimized for Noctua 200mm" which must mean they are pretty low density.
The finstack is the same as MORA 3. MORA can be used to passively cool but the fins are stacked so that a low static pressure fan can fairly easily get air through so you dont have to have a ton of loud fans and it stays quiet and cools.
 
I've been running dual MORA3 420s, each with 4x 200MM Noctuas for about 3.5 years now.
I actually have them sitting on a shelf, one in front of the other, cooling an 11900k/3090

The only time the fans go over 400rpm is when the room just gets too hot and they have crank up to keep things cool. It's enough to keep the hottest build cool without noise - assuming you can keep the room cool.

You could crank up the fans or get more static pressure but it just doesn't make sense unless you have it looped into several systems which I have no interest in doing.

It's kind of stupid in a lot of ways but it does exactly what I wanted it to do - silence any system I could imagine, without compromise.
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I think of more concern with Rads like this is flow rates. There is a mile of pipe here. My guess is it looks to be a four-time parallel layout (typical MORA) through 80 tubes or approx. 33 meters (not mm) of pipe running through the 200mm fan optimized MO-RA IV 400 fins. In terms of head pressure, I'd be most interested in seeing a dual DDC vs D5 flow rate comparison in series and parallel. One thing I have learned using large radiator is flow rate is more important than static pressure. In other words, I've never had to worry about going push pull fans to get desired performance. That wasn’t the case with monsta rads for example push pull was a definite plus. I use Air Series SP120 PWM fans. They max out at 2300 RPM. All fans are set in bios with PWM curve. When gaming they rarely exceed 700 rpm and with 100% load stress testing ramp up to 1100 avg or 1200 max rpm. I guess my point is I attribute the performance to the dual D5 pumps not how well my fans push air through the rad. However, the MORA (four-time parallel layout) is a totally different rad config than my Nova which is actually 3-360 rads in series. There may be a good reason why the MO-RA IV 400 addon is a dual D5 pump setup which look awesome btw. Bottom line sweating the details with such a large rad is superfluous.

My setup custom built cart sits below and behind lift desk.
View attachment 678095
MO-RA IV 400 w/dual D5 + Res
View attachment 678096

While the length of tubing is indeed long, at least in my prior experience with radiators, it is rarely particularly restrictive.

I have been doing something somewhat unusual in my last couple of large builds.

Because multiple pump scaling is usually pretty poor, I have instead split off various segments of the loop to different segments, pumping out of the same reservoir, and returning to the same reservoir and mixing there.

In my current build, I have dual D5 pumps pushing water through my radiators (1x 420, and 2x 480) and a single d5 pushing water through my two blocks (GPU and CPU).

The funny part is that at full speed, I see crazy overkill flow through my radiators, and rather underwhelming flow through my blocks. And the blocks are more flow dependent than the radiators are. Hindsight being 20-20 I would probably have reversed it. Dual pumps through the blocks and a single pump through the radiators.

I'm - in my head - picturing getting two Mora 600 IV radiators, with one dual D5 loop pushing through both the MORA radiators, and dual D5 loop pushing through the game loop (1x CPU block + 1x GPU block).

I also intend to have a secondary single pump loop push through a single CPU block in my main server.

The only downside here is that the Watercool MORA integrated reservoirs and pumps don't support having enough connections for multiple loops.


I am reluctant to go with th elow static pressure 200mm fans, but maybe - just maybe - I'll go with some hotter 140mm fans.


In my application I don't care about noise. The radiators are planned to be mounted to the side of my server rack, which is in a separate room 50ft away from my office. I'd happily crank up the fan RPM for more performance, but it seems like with the low fin density these MORA radiators use, there may not be much benefit to going with higher static pressure 140mm fans.

1725892391595.png


I'm picturing taking the side panel off of the rack, drilling holes for the wall mounts, attaching one or two MORA's to it, and hanging the side panel back on the rack.

The MORA(s) would be responsible for cooling both my desktop (currently in that Corsair 1000D, but the intent is to build it into a rack mountable case)

The loop would cover the CPU and GPU for the desktop as well as the CPU on the server.


My inclination is to use Noctua 140mm iPPC 3000 fans, but I'm guessing 140mm fans at 3000rpm, with 160 CFM airflow and 6,58 mm H₂O static pressure may be a combination of total overkill and not entirely useful here, which is a shame.
 
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For shits and giggles, I shot an email to Watercool's support about the fin density.

The answer I got was as follows:

We have chosen the fin geometry so that the Noctua NF-A20 HS PWM
performs very well on it. In addition, the cables can be laid very
easily. However, you can also use 16 x 140mm fans, in which case the
cabling will be more difficult and the performance will not really
increase. If the noise level is not an issue, I would use 9 x 200mm
Noctua NF-A20 HS PWM.


So even in a setting where noise is not an issue, they still recommend the 200mm fans.

It sounds like the 140mm option is just there for good measure to placate people who might be fans of 140mm fans.

That is almost a little too bad.

I would have loved a version that requires more static pressure to really get the most out of a radiator this size.

In my potential application I'll be putting as much as 1500w through it between two systems, and I like my delta T's as low as I can get them :p
 
Large capacity fan coils and hobbyist grade watercooling gear aren't what I consider a good mix.
Step up to real industrial pumps and plumbing and don't look back. The results speak for themselves.
If your load is high enough (10kW+) you're in Koldwave territory or just move to a glycol based water to water exchange system with the fan coils outside. Entry level datacenter cooling is definitely overkill for (most) home users though as 25kW is half the capacity of the typical residential electrical service. And those of you with larger homes with 1600A service, many are connected to the primaries with a 50kVA transformer so that presents issues.

Personally I like geothermal. It just works and silence is golden.
 
My inclination is to use Noctua 140mm iPPC 3000 fans, but I'm guessing 140mm fans at 3000rpm, with 160 CFM airflow and 6,58 mm H₂O static pressure may be a combination of total overkill and not entirely useful here, which is a shame.
It would only be overkill if you never had to use it. ;) otherwise it would be nice and quite.
 
I bought mine direct from Watercool.

That's how I got my Heat killer IV Pro block for my Threadripper five years ago when FrgMstr reviewed how shitty the EKWB Threadripper block was, and highly recommended the Watercool block

I've been buying as much Watercool stuff as possible since then. They appear to be a good company.

I ordered it straight from Watercool in Germany. Just take the prices on their webpage, subtract VAT and add shipping.

I've ordered like this straight from EKWB in Slovenia a few times too, when no one in the U.S. had a block that fit my GPU in stock. Won't be ordering from them again any time soon :p

It's not that bad. (Though I imagine returns might be difficult if you have problems, but that's a risk you take when you are into this stuff)


Shipping may be a little bit high for something as large as a MORA, but usually I am surprised how reasonable it is when I order from Europe.
 
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It would only be overkill if you never had to use it. ;) otherwise it would be nice and quite.

They seem to suggest it is much more difficult to wire the fans. I guess the 16-up 140mm fan bracket doesn't have a fan header for each fan like the 9 up 200mm one does.
 
Still loving my MO-RA 3. The only downside I found was it is difficult to get the fan wires crammed between the 120mm fans. My Phanteks T30s and Artic P12s are all daisychain fans, which actually makes things a little harder as you have a connector to deal with on each fan instead of just having a thin cable to run all the way to the side. If you buy some brand of fans that click together, it would be optimal.
 
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