After over two years in production, the Antec P180 and its derivatives remain extremely popular not only among PC silencers but PC enthusiasts everywhere. Despite its many strengths, one criticism has been that air inflow could be better, especially when the front door is closed. This is an issue that has become more evident as gaming video cards increased in power & heat. There are several threads here in the forums where comments about the need for more air inflow has been loudly noted.

The primary bottleneck is a fairly minor one: It's the hinged doors that cover the intake vents behind the main front door. These doors (there are 2) are designed like angled venetian blinds, but with one major difference, which is the flaw: Rather than being of constant thickness, the front edge of each slat is quite thin but considerably thicker on the back side. This makes the cross section profile of each slat a sharp triangle, if you can picture what I mean.

The photos of the intake covers below help to illustrate what I'm saying.





When presented with these covers while working on the prototype design, I expressed concern about potential airflow restriction; the slat design was not exactly what I had intended. Antec did not wish to incur the cost of retooling the mold for the part, which is apparently quite expensive. (At this point, they had no idea just how successul the P180 would be...) Also, real system testing at that stage showed that the case had no problems with cooling the hottest components around at this time.... which was pre-SLI. So, the grill was left unchanged.

Flash forward 3 years. Dual vidcard gaming machines are commonplace, as are 150W GPUs. The biggest issue with the P180/182 is cooling of high power video cards without incurring more noise. There are many simple solutions for just cooling alone -- but cooling without additional noise is more of a challenge.

Here's the simplest way to improve the airflow in a P180/182/190 without adding more noise: Remove the cover grill doors for the front intake vents. Just push down a bit on a small tension tab near the top pin hinge and the plastic cover grill will slip off easily. This will drop overall temperatures in most systems. By how much is difficult to say, it depends on the details, but I'd guess at least a couple of degrees overall for most systems, and probably more for very hot ones. You could also remove the dust filters as well for a bit more improvement, but that will leave the metal visible whenever you open the door -- which might not be an issue if you leave it closed most of the time and wish to have the highest airflow. With the filters on, the black face is still mostly uninterrupted -- you can easily paint the metal that's exposed.

The metal grill behind the dust filters present much less restriction; the metal only covers 10-15% of the total area. Removing the metail grill is something diehard modders will still want to do. If you do, take care not to cut the holes for the filter clip and note that there's more of a chance of EMI when the aluminum door is open.

Note that the grill all around the sides, top and bottom of the front bezel/door is quite open and provides very good airflow access when the front door is closed. Still, opening the door after the vent covers are removed may give a bit more airflow improvement, but at the cost of more direct path for sound between user and the noise producing components inside the computer.

FYI, Antec finally agreed recently to replace the vent covers for a more open design. It's not clear exactly when this change will occur in the production line, but I'd guess that it will not be a major announcement, just a running change on the next run after the new cover is ready. I'm also not sure exactly what the new cover design will be, just that it'll be much more open. (I'm not involved in the current evolution of the case and was not involved at all in the P190 design.) I've asked Antec to make the new cover available for existing P180/182/190 owners to retrofit if they wish; it probably won't be free, but I expect it'll be quite reasonable.

what about cutting most of those out, and then stretching pantyhose or that cloth they put on speakers over the top? That might be just as restrictive.

Hey Mike:

First, thanks very much for pointing this out. I'm about to start a P182 Build very soon and it will include a Geforce 8800 Ultra. So this news come very handy.

Would you please let us know in this thread, once Antec decide to put their new vents on their site?

Again, thanks a bunch for this....

Good update for the community. I find that the small doors are purely aesthetic, and even then only if you want to go for the retro server look. They should be the first thing to go on any new P180.

Other things can go too... the PSU scaffold, the bottom middle fan mount, and the bottom chamber divider for instance. Since the bottom chamber will typically be cooler than the top chamber these days, increasing the flow through the bottom front vent and into the top chamber (by removing the divider) can help the big picture. The bottom fan usually goes because it gets in the way of the PSU cables and it works poorly in that position, blasting against the case more than through it.

I run a P182 with the small doors removed, metal grill snipped, fan filters on, and main door shut. Back vents sealed up. With two output YLs and one input all at 5-7v, the negative air pressure is significant, so I use two methods to increase free flow: no bottom chamber divider, and a semi-open 3x5.25" -> 4x3.5" hard drive bay (ala kama bay). This spreads the load on the side slats when the front door is closed because more flow is coming in from the top and bottom of the front of the case, rather than just the middle and some from the bottom. This also sustains my goal of having most flow pass through filters to remove dust.

This setup is very quiet and effective for me with a 2ghz 65nm Core 2 Duo and a Geforce 7800-class video card. The top fan spot could be sealed for less noise, but that extra output will be necessary for hotter systems.

The openings on the front panel should look like this when you are finished:

In bad lighting:



And too much flash:



Tin-snipped, nibbled, and smoothed with Dremel.

Hmm, I removed the door and temperature remained the same throughout. Most likely cuz I'm not pushing enough air in the first place. I'm using the tricool fan running on low.

What I did find that helped tho, prior I taped up the side vents because I read that it will be good for over system cooling. So I decided to remove it and my video card temperature dropped something like 3 degrees. I have a vf700-alcu on a 7900gs clocked at 640 core / stock mem. I get temperatures of like 69 degrees while playing stranglehold. Most other games I get like 65max.

Mike, Antec owes you big time for helping them with this design! It has been a hugely successful case. I hope you were compensated appropriately.

I'll plan eventually to mod those "front doors" simply by cutting the those bars out, leaving the frame and attach some black mesh panel with epoxy. Less restrictive I hope. And it would keep nice look. Oh, well, I need to see when I got time to make this mesh mod.

Great post. I took the doors off my P180B immediately and closely examed the vents. The cross section of the "slats" look like
--------------------------
Fron
_
|
|
|
----

Back
--------------------------
rather than a strickly triangluar shape.



So it's possible to just cut the back piece of the cross section out and imporve airflow without sacrificing the front door all toether. I couldn't resist but started giving this a twirl using a utility knife. This is definitely possible. The cuts would also be smoother using a dremel. This would be a welcome mod for my planned 8800gts or 8800gt (if it's any good when it comes out) purchase.

You guys still have the little square holes on the side of the front bezel to deal with....that's where all the air enters if the front door is closed. Some creative Dremel work on those holes could provide more total intake area, and a smoother airflow.

+1

I don't think these are much of a problem unless you're trying to run all your fans at high speed. The total area these holes represent is pretty large.

Each side hole measures ~4.5x17mm. There are ~75 per side. That's a total of 11475 sq mm. Plus the bottom slot vent of 136x17mm -- 2312 sq mm. Net area: 13787 sq mm.

The blade area of a 120mm fan (counting the spaces between/around the blades as well) is 11309 sq mm (the area of a 120mm circle), so the total area of the circumferential bezel vents -- about 22% bigger than the area for a 120mm fan.

If you're running 2 or 3 120mm fans quietly at slow speed (which is realistic for a fairly powerful well designed system with high performance low-airflow heatsinks), I think that's a big enough intake area to give you decent temps. I haven't ever heard increased turbulence by closing the front door. This might happen if all the stock fans were set on high, but it's moot as the total noise would be way beyond what SPCR is interested in. (Probably >50 dBA/1m).

Just open/close the door when/if thermally controlled fans ramp up or when temps go up and you need more airflow... which, for most users, will be when you're gaming, when the game sounds will dominate your concentration and you won't notice the 1-2 dB increase in noise from the front of the system under your desk by keeping the door open.

Hmmm... interesting. I guess I should have ripped one apart. But like I said, the simplest fix is to remove it.

Actually I'd also remove the dust filters too, as they're kind of restrictive. I have a bit of a dust problem with a long hair cat, and when the filters get clogged, they can certainly impede flow and cause temps to rise. The inside still gets dusty anyway, even with the filter. When the inside gets dusty, the temps hardly rise all, while as when the intake filters get clogged, temps rise quite a bit. See Sticky: Low air resistance, low fan speed, low noise technique (in this forum) for a discussion of dust filter vs. regular internal system cleaning.

MikeC....I'd probably guess that the total area of all the little vent holes doesn't matter as much as the holes closest to the fan(s). The vent holes furthest from the fan are not of much benefit to the airflow.

I'll bet you could check this easily by using tape over different vent sections...see which of the vents makes the most difference to the temperatures. I'd try it but I don't own the case.

@MikeC: I have the P150 and measured about 50 cm2 vent area, so the P180 should have around 70 cm2, if the vents are the same size, are they?
A couple of months ago I mentioned a different kind of vent system that would increase the vent area 3 times, while denying a direct sound path.
It would fit in the same area as the P150 door, but it wouldn't be a door anymore - that hinge wastes a lot of vent space.

Not the same size -- each circumferential bezel vent hole in the p150 is about 8.5x3mm. The holes on the p180 are more than double the size at ~4.5x17mm. The plastic material between each hole is the same in both -- about 2.5mm.


And where's this post?

Thanks for the info Mike

Please make sure they let us buy the new grilles so we can retrofit

Oh, and did they tell you a reason they won't release the P190 w/o the PSU's?

You're welcome.... and that decision is theirs but I'm sure they will.


I'm quite sure they will soon if they haven't already.

@MikeC: the post was on the 9th July, but it didn't provide any details. Anyway, since I seem to have your attention, here is a picture of the design:



The plastic slats at 45 degrees should help block the sound, while allowing good airflow, they are 2 mm thick and about 6 mm in between.
This is for P150, my 'dream case' has slightly different sizes - 5 cm LONGER than P150 and 2 cm wider (uses 14 cm front and back fans).
Obviously there is no room for door hinges anymore. And I don't know how to manufacture the structure above, I tried to find someone who knows.

Thanks for the very helpful post, Mike. Pulls things together into a useful authoritative note. I wasn't aware of the EMI risk that comes with cutting out the steel grills. I'm assuming this risk comes with cutting out the top and rear grills as well, right? Could you say anything more about this?

I wonder why Antec didn't consult you on the P190? Reviews that I've read have been mostly favorable, but my hunch is that you're review would be much different, and rightly so.

It looks good, I'm sure it'd be simple to manufacture, but it won't work on a P180. Would do on a P150. Still, I don't think those bezel-surround vents present any serious airflow restriction in either of these cases, so I can't see Antec retooling for this. But for a new case, yeah, nice idea.

The effect of EMI is mostly on cordless/cell phone reception, and it's not 100% consistent -- ie, some PC gear doesn't seem to emit much EM at all. The only time I actually noticed real EMI was using a cordless phone at a testbench unenclosed system. I moved 10' away and the interference stopped, so... Some warn about the long term health effects of such exposure, citing mysterious cancers, etc.

As for the P190, I guess the Antec design team felt they didn't need my help; got all they needed to know from the P180 and Fusion builds. It's also aimed less to silencers and more to the performance market.

Because of the thinness of the p180 plastic sides?

PS: On dust:

Not all houses have the same kind of dust. If I ran without good filters (and I have for years), fan blades get thick buildup along their leading edges, and fans themselves get gummed up on the inside with dust, breaking early. This can start after 2 weeks. So in this way, some people really need the filters.

Also there is a time and convenience factor. Cleaning a case every two weeks is a bigger hassle for me than cleaning a filter every week. Cleaning a case properly is not a small job, and the last thing I want to do is have more things to clean.

My conclusion about input filters is this: If you want to keep dust out of your case, it is worth having the filters, with no doubt in my mind. The flow change is not a deal breaker for me at all, as I have discovered with the P180. I won't buy a case without robust input dust filtering, and haven't since the 90s. I bring this up because I want that part of case design to continue to be developed.

I just removed my hinged "dust filter" doors. It didn't change my speedfan temperatures but I sure would like to remove air restrictive parts.
Most of the air probably got through my Kama Bay before the change so my graphics card got 2-3 degrees cooler now (reported in ATI Overdrive).

My CPU temperatures get higher with the door closed though.
Leaving the door open is more efficient on my computer.
It might have to do with the extra front fan that I have in my Kama Bay.

What do you think about the dust filter on the Antec Nine Hundred (gaming case).
http://www.antec.com/ec/productDetails.php?ProdID=08009
The solution seems simple, have low air restriction and it is "modular".
Isn't this a good solution except for the direct noise path (no door)?
Edit: I meant shouldn't Antec adopt this dust filter for a possible successor to the P182 case.

Also there is another interesting thread were other kind of improvements are proposed to the P182/P180B case.
http://www.silentpcreview.com/forums/viewtopic.php?t=42223

The Nine Hundred is an excellent case if you want to run a high end system silently. As it is quite open, you need to select silent components in the first place though. Quiet, suspended HDDs and a good CPU cooler.

Any loud components will be more audible in the Nine Hundred than in the P180. However, it's not clear cut because, for example, three Yate Loon fans at 5V will still be quieter than one Yate Loon fan at 12V. For a high end system, the Nine Hundred might be better.

I have been having this discussion in private with EsaT and on this forum for a while now. I am currently ill but eventually want to move my system from a P182 to a Nine Hundred and compare. I think it will probably be quieter, because I find suspended HDDs better than the P182s soft mounted HDDs and I hope to run the fans at a lower voltage.

When it comes to doors, I think my current server case has probably the best door I have ever seen on a computer case. It looks a bit like this:



The overlapping slats are very large and allow a lot of air to move (almost unrestricted I would have thought), yet the indirect path means sound is reduced.

IMHO the ultimate case would be a Nine Hundred with that kind of door on the front. Well, maybe the Twelve Hundred with built-in water cooling will be a contender too.

Well I do not think so.
The Nine Hundred has to many holes (direct noise path) and worser side panels (dampens noise and vibration a lot less).
I don't think we can compare gaming cases to "SPCR silence standard" P180/P182 cases. I am sorry.

Can't you softmount your hard drives in a P182?
I have done it with my scythe enclosed hard drive in my P180B.

I was only referring to the dust filter solution Antec adopted for it as a possibly better and smarter option than the existing one on the P180/P182.
With a possibility to mount a fan on the upper 5.25" slots it could make a "Kama Bay" like option.

Any more suggestions for dust filter improvements?

BTW, "Mr. B"'s Your Basic P180 Rig - Sans Fan Grills - Filter Door Mod describes a way to trim the excess off the front grill slats.
http://www.silentpcreview.com/forums/vi ... hp?t=42020

It depends on the system. If you put a fanless Epia board with fanless PSU in a Nine Hundred, it would be silent.

Okay, that's an extreme example, but consider this. I currently have a QX6700, 8800 Ultra, 680i mobo and two HDDs in a P182. I need to run the fans at about 10V to keep them from overheating. The system is a bit louder than my old one, which has a similar number of fans but all at 5V (plus an Eheim pump). Even with the door of my old system open and two suspended HDDs and two 5V Yate Loons exposed, it is quieter.

Both systems are very quiet but I think the P182 system would be quieter if it was in a Nine Hundred, because despite being a more open case the things inside the case would be quieter as all fans could run at 5V and the HDDs could be suspended.

What make and model case is that?

OK, I got your point.
I should have read your post more carefully, I am sorry.

And Mike thanks for your links and all you do and have done for us.
I repeatedly realize I still have a whole lot to learn here.