HAF 935 Insanity


[H]F Junkie
Jun 12, 2012
Well I've gotten hold of a new case again, this time it's a CoolerMaster HAF Stacker 935

The case came in what is quite a large box, I was a bit worried that the case might be larger than expected and won't fit to it's destined place.

In case you were wondering. No, I'm not sponsored by CM, and won't ever be after this review :)

It's only coincidence that all the components I've gotten are made by CM. I was looking for high airflow fans, and was actually going to buy Aerocool Sharks, but the retailer went nuts and almost doubled their price just days before I ordered.

After unpacking it, my worries were alleviated. It's not as big as the box suggested.

After attaching the 915, it is impressive in size, but not huge:

And I instantly have a beef with CM. They advertised it as an unit that can house two PCs if needed, but the 915 came without controls, it only had a blank piece to cover the hole where the USB plugs and the Power switch should be. It's not a cheap case at $250, but making me buy a second set of controls separately is cheap on behalf of CM.
Thankfully I was only thinking about putting my HTPC/Router/Server PC in it, but after seeing how much space is left after installing my main PC in it, I quickly scrapped that idea. So I won't be needing that second set of controls after all.

Let's look inside:

Nothing new here, same old layout as all tower cases.

The case comes with only two fans installed one 140mm at the back of the 935, as an exhaust. And one 80mm at the front of the 915 as an intake. And they're both the cheap kind, that will probably wear out in 6 months or less, and not very efficient anyway.

Since I didn't have spare 80mm fans I left that one, I'll replace it if it wears out. And it's only for cooling the HDD cage anyway, so it's adequate for that purpose.
But the 140mm had to go, I replaced it with a 140mm Jetflo, from the Nepton, as only 120mm ones are available to purchase separately currently.

The HDD cages have some sort of Quick lock mechanism, but it's completely redundant, as it's locked in place by no less than 6 screws. And if you remove those then the mechanism is not rigid enough to safely hold the HDD cage, especially if you fill it up with 3 drives. This is such a childish design flaw, it's pointless but nonetheless it raises to cost of the cage.

You even have to take off the bezel to get to the screws holding the tray from the front.

I don't know who designed the intake vent for the PSU at the bottom, but it's not even close to matching the shape. But I wanted to install the PSU in the 915 anyway, to leave as much clear space for the VGA as possible.

Next thing I noticed that while the top of the 935 has some big holes in it for airflow, the bottom of the 915 is almost fully closed.

How will there be "high air flow" then? HAF my ass, more like NAF, as in no air flow. Of course you can say they intended the two cases as completely separate compartments, but then the 935 has absolutely no advantage cooling wise compared to any old tower case. You'd be stuck with a single 140mm exhaust fan at the back. Which unless you don't care for noise is far from enough. So I decided this will not do, I cut a large hole in the bottom of the 915:

That will allow me to set up the cooling as I intended originally, to install exhaust fans on the side of the 915, and obviously I wanted to cool the whole case that way not just the upper half.

I also had to cut small hole near the front drive cage (upper left corner on the picture) to be able to connect the SATA cables to the drives there, because CM didn't think about that either. They expect you to route the sata cables all the way back to one of the small holes they made in the freaking center of the whole case, which is sure to make a mess of things, and you need extra long SATA cables too that way.

Of course I had to make the same cut on the top of the 935 too:

After wasting half the day on correcting these issues, I was finally ready to install the MB. Boy was I in for a surprise. CM should fire their whole manufacturing department. I haven't seen this crap workmanship on a PC case for 15 years at least. It took me an hour, yes ONE WHOLE FREAKING HOUR, to insert the spacers for the motherboard, the threads were so badly made, that 3 out of eight of the pins wouldn't even catch on to it. On the rest I was able to tighten the pins with a socket wrench, but for those three, I was thinking about drilling out the thread, when finally after putting so much weight on the wrench that the MB tray was bent I was able to force them in.

At this point I became so frustrated that I didn't even bother to document the rest of the build, so it will be text only below.

I replaced the controls of the case to the 915, and put the blank insert to the 935 to have the controls on the top, but CM didn't figure someone would opt for this configuration, as the cables aren't long enough. Thankfully the USB 3.0 connector is on the front of my MB so that one connects fine, but I wasn't able to connect the USB 2.0 outlets, and the power switch only reaches the pins barely. There is really no 5mms to spare. Some would say lucky, but I say stupid CM, this supposed to be your flagship product, think of everything when designing it.

Next task insert the radiator of the Nepton, I always wanted it in the 915 but also wanted the psu and one of the drive cages there. This meant that I had to place the radiator into the middle of the 915, but that's only possible with 120mm fans, that's how I salvaged the 140mm jetflo for the 935's rear exhaust vent. Well installing the radiator wasn't easy as I tried to do it with the PSU and front drive cage in. I'm not putting this on CM, I could've assembled it in a different order. But it was manageable. And the hole I cut on the bottom came in real handy, I don't think it would've been even possible for one person to install the radiator in this configuration normally. The big holes also some in handy for routing the water pipes trough them as the hole intended by CM for this purpose wouldn't work, it's just too far back, you'd risk breaking the seals by stressing them too much. Since I had to install the radiator vertically, horizontally it's at least 180mm, so it would extend into the PSU in the back, or the drive cage in the front.

Another annoyance of mine during the build was that the rubber covers on cable routing holes kept falling out, especially on the bottom of the 935 which I didn't even use. It was already out of place when I unpacked the case from the box.

The final configuration I ended up using is two JetFlo 120mm fans on the front as intakes, and two of them on the right side of the 915 as exhausts, and one connecting to the left side of the 915 and feeding the radiator as an intake. And of course the two 140mm JetFlo fans that came with the Nepton, one pulls air off the radiator, and one as an exhaust in the back of the 935.

If there is one good thing then it's this: The White JetFlo fans really look good in the case, and really suit my fan controller that's also illuminated in white. The only thing ruining the harmony is the red power led of the HAF, I'll check if I can replace it with a white led tomorrow.

But speaking of controlling the fans, the six 120mm JetFlo fans came with two adapters each that were supposed to run them at 1600rpm 26 dB or 1200 rpm 19 dB according to factory. Well someone screwed up at CM in this case too. As the higher rated adapter runs the fans at 1750-1800 rpm, and they're still unbearably loud then. And the smaller adapter runs them at 1400, instead of the supposed 1200, and for me they're still too loud, I couldn't bear the noise. So I ended up throwing out all the adapters and connecting the fans to 5V. I was worried they wouldn't even start at that voltage, but they did. And the noise level is now at a level that I can live with.

Now the system is up and running, but I didn't bother with cable management in the end, so it looks like a mess in the 915, so I'll have to work on that later, and I'll try to make more pictures when I decide to take care of the cables.
So after settling in, I have to admit, that cooling performance is really great. Even with the top vents fully covered. I don't know how much my "modification" contributes to this, but my R290X DC2OC never even spins up it's fans while gaming. With my Sharkoon Rebel 12 Value, it was full on a few minutes after loading a game. Now all is quiet. It's much better than the Raven RV03 too. CPU temps are not changed however, but that's expected since I'm using watercooling.
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Every experience I have had with cm has been lousy. Reading this doesn't improve their odds of me buying from them
I've just said in another thread a few days ago that I don't consider them to be a first tier manufacturer. This experience certainly didn't change that opinion. At least not in the right direction.

I wrote to CM support and they act as if this is a unique case, of a faulty product. But I'm not convinced. I think they're just using shitty manufacturing procedures. I have the same problem with the fan bolts of the nepton, They're impossible to tighten by hand, even with a screwdriver it's difficult to tighten them. And those are supposed to be tightened by hand. But the same goes for expansion slot covers as well. They're not pleasant to move by hand the threads are so bad, or the bolts who knows, which one of the two is crap.