Quiet Overclocker's Antec Three Hundred case mods

[Hangfire]

I've built many PC's, but getting them really quiet always took a back seat to time, effort, money, and performance. After a few unsettling experiences with noisy builds, I decided this next system would be quiet from the start. The goal is to allow core unlocking and moderate overclocking, and future upgrades, while maintaining quiet.

System h/w is:
ASUS M4A89GTD PRO/USB3
AMD 550BE 3.1GHz
2x1GB Corsair 13333MHz DDR3
Corsair 400CX P/S, 3xScythe 120mm PWM fans
Thermalright 140mm 3-pin fan
Scythe Mugen 2 Installed now!

And oh yeah, an Antec Three Hundred case,a late model with CPU Window in the tray. Onboard HD4290 will be used until overclocking is fully wrung out (and Steam Linux client is released).

First, a YouTube video of painting the case black. I started modding the front case fan cages and then gave up on that as they did not allow enough room for the louvers.

http://www.youtube.com/watch?v=izrukbz40-4

Next I added material to the side panels. I experimented with PlastiDip, vapor barrier, and craft foam on one panel, the other was craft foam, vapor barrier and craft foam on top. The idea is to get multiple densities of material layered to catch different frequencies.

A few Idle temps:
System in old server case with 80mm fans: CPU 37C
In Antec 300 case with stock AMD cooler: CPU 34C
With Scythe Mugen 2 Rev. B: CPU 30C




Case panels nearly finished. I had to remove a couple of layers in an inch-wide line where the back of the panel engages the rear pillar of the case. Blue panel is PlastiDip/vapor barrier/craft foam 3-layer, black panel is craft foam/vapor barrier/craft foam 3-layer.


Serious jigsaw bimetal blade and Dremel tool work to make room to seat fans flush, and fan set inside for a test depth fit:

[Hangfire]

I've heard of reversing the panels on the Three Hundred, but I've never heard of anyone cooling the backside of a CPU socket. If it's making 140W on the front, I would imagine a little of that heat might be coming out the back? I've pulled down old overclocker's motherboards where the white cpu sockets were tan or brown and crumbled when touched.

Here, a Scythe Ita Kaze HDD cooler does the work of cooling the back of the motherboard. This 100m cageless fan and heat sink is very, very flat.


Next, I build separate ventilation for the Corsair 400CX. Here, half the holes are punched air to come in. Holes are well forward of the P/S in order to prevent a direct line of sight between the P/S fan and the outside world.


After the rest of the holes were punched, a shroud is then built to give the P/S its own private air supply. A little bump of high density black foam is used to block direct line-of-sight. Air has to go over this bump, which it does quite well. P/S is mounted fan side down, on thin foam pads glued to the top of the mounting tabs. A P/S gasket was created from black foam as well.

[Hangfire]

Again, to prevent direct line-of-site between the front case fans and the outside world, or at least the user's ear for a near-floor based system, a set of louvers or venetian blinds are created. A red oak frame plank from a home center, 120mm holes cut with a jigsaw, and then cut louver slots at 45 degrees on a compound slide miter saw, then filled with siamesed tongue depressors does the job. All gluing by underage child labor.



A two-pin header connector was split and the (red&black) wires soldered together to bring the PWM control signal to the fourth pin of the two front PWM fans. Two 3-pin fan headers had one side removed (Dremel) to fit onto 4-pin PWM fan header connector. Tachometer signal from front fans is discarded and the system uses the RPM signal from the rear chassis PWM fan.

Test fit of front fan mount/louver system. Screw heads need a little black paint. Dust abounds.

[Hangfire]

M/B was installed and removed about a half a dozen times. Chassis punch holes were created for proper cable dressing. System now needs a CD/DVD SATA cable, Mugen 2 CPU cooler, and hard drive suspension. Using Thermalright rubber fan mounts for top 140mm TR fan and back Scythe 120mm PWM fan.



Detail of front fan PWM signal tap. Green wire has since been routed under M/B.


Nearly completed case back. Asus was nice enough to put some padding on the back of the I/O shield. I didn't bother to paint that, not sure why. Back of PCI slot covers are rubberized with PlastiDip, thus the different texture.


All images uploaded with ImageShack.us

[Hangfire]

Using a compass, box cutter, and a leather hole punch to create a 140mm fan gasket:



No perfect, but close enough:


Rear 120mm fan gasket, top 140mm fan and gasket, and PCI slot cover foamies installed:

[Hangfire]

Cable routing on backside, through holes cut with knockout punches. I had to tie back the cable going straight up to make room for the CPU window fan. I added a 3 pin connector on the back side for the window fan to allow for easy disconnection when pulling just that panel. Then I had to cut channels in the panel foam to allow clearance for the side panel to close fully.





CD Case modified to become quiet drive suspension. Top of case on left flips over endwise so that smallest piece of foam is near the drive connectors.



(Images uploaded with ImageShack.us)

Mugen 2 Rev. B installed. SATA cables need a little arranging.

[frenchie]

You're quite a modder !! Are you going to put a GPU in there ? Cuz that's a lot of fans !

[Hangfire]

The plan is to wring out overclocking and core unlocking using the onboard video (which itself is overclockable). Then in the future, perhaps after Steam releases its Linux client, go to a discreet video card.

I am taking it one step at a time because AMD introduced a lot of uncertainty into overclocking the unlocked 550BE/555BE when they decided to disable core temperature sensors in the unlocked firmware they released to motherboard vendors. I'll have to either chart other temp sensors in locked mode and correlate against unlocked mode, or get one of the old-school temp sensors that wedges between the cpu and the cooler.

I'm adding all the fans at the start because I found that over time, I'm much more likely to upgrade the hardware than re-mod the case. I also had a bad experience with system temps and an 8800 Ultra, so I wanted to start with a system with two front input fans.

-HF

[Hangfire]

(I've updated the photos and the temps. Actually I'm running more 28C to 29C most of the time now, probably because the Arctic Silver 5 has had time to cure.)

This is my, I don't know, 20th or 30th build or so, but the first one where I modded extensively for quiet up front instead of reacting in self-defense. I am pleased with the results, especially the reduction in CPU idle temps from 37C (when tested in an old server case with 80mm fans) to 34C in this box to 28-29C at idle with the Mugen 2 installed.

System makes a low pitched woosh noise that is pleasant and not noticeable at all if anything else is running. The only computer system I've had that was more quiet was an Atari!

I feel I have met my goals of this build (so far, we'll see how well the components overclock). However I learned some things and still haven't found the perfect case for combining overclocking and something resembling quiet.

While I am very impressed with the quality and value of the Antec Three Hundred case, I have a few issues with it.

• First, a small cosmetic niggle, the front mesh is applied diagonally on the 5-1/4" bay covers and vertically on the rest (front air intake). It is a small thing but I think it would look better if it were both matched and aligned.
  
  Second, the bay covers should be vented or have an option for venting, like a knockout center to the plastic. The mesh is already there! Since the CPU lines up with the top bays, and with all the fans in the top and back, some airflow would probably come through to cool the hard drive or bottom/top of larger bay devices. I may do this mod myself at some point, especially since it doesn't involve pulling other components out.
  
  Third, both front fans blow on the card slot/video card area and don't line up with the CPU. While this doesn't seem to hurt temps much, I would prefer to have some in-line BTX style CPU cooling.
  
  Fourth, there is no other outlet for all that air below the card slot/video card area except the power supply. If running big cards in SLI/CrossFire, the poor Power Supply is going to get cooked with GPU heat. A high quality power supply rated for 40C operation is probably going to be OK, at least for a while, but the fan noise level is not! A cheap P/S rated for 25C operation is not going to last long.

I love the looks of the case and the stealth nature of mods.

I guess my problem with this case is it was designed for mostly diagonal flow from lower front to upper back, while I would prefer three levels of airflow from front to back- top for CPU, middle for GPU, bottom for PSU and maybe HDD/SDD. The GPU should have a 120mm evacutation fan as well as the top for the CPU. The bottom flow could be handled by the PSU fan.

Still, I can't complain for less than $50 on newegg special, delivered.

If anyone has suggestions for my ideal case, I'd like to hear them.

[danimal]

i think that you've done about all that can be done with that case??

nice job... as soon as your ship comes in, get a p183.

[speedkar9]

Fourth, there is no other outlet for all that air below the card slot/video card area except the power supply.

Well thats what the 120mm side panel fan was for originally . If you have a passive video card, you could probably rig up something to have a fan mount in the expansion slots below.

If anyone has suggestions for my ideal case, I'd like to hear them.

I too was also thinking how to mod the 300's front panel, using a piece of metal to block the direct noise path.

I think if you converted your HD bays into 5.25 by reriveting the drive walls further apart, you'd be able to suspend your hard drive in the lower compartment.

That would free up the front air intake across your CPU and GPU, whereby you could experiment with ducting, and compartmentalize your case. Mid-mounting your front fans could help keep the noise inside of the case and direct it at components that need it most (like BTX).

Cheers, and happy modding !

[Hangfire]

I too was also thinking how to mod the 300's front panel, using a piece of metal to block the direct noise path.

That would be cool, but woodworking is easier for me than milling...

I think if you converted your HD bays into 5.25 by reriveting the drive walls further apart, you'd be able to suspend your hard drive in the lower compartment.

I thought of that... after I had already cut the metal. I have a rivet gun (or two) so it would have been no problem... I'm already thinking about the next case.

That would free up the front air intake across your CPU and GPU, whereby you could experiment with ducting, and compartmentalize your case. Mid-mounting your front fans could help keep the noise inside of the case and direct it at components that need it most (like BTX).

Thanks. I'm actually pleased with the front air input on the 300. My issue is with venting the "hot pocket" below the video card(s). I don't like side vents (direct sound path, from about the worse place imaginable). What I would like to see is a fan in the back between the card slots and the power supply to remove GPU hot air. This may not be possible in a mid-tower format like the 300 unless I flipped the motherboard tray and left the P/S at the bottom. The P183 might be a better candidate for this mod because it has the middle shelf to anchor the flipped and unflipped parts together (M/B and P/S respectively).

There is a customized case sort of like that in these forums, or this LIAN LI PC-V1200Bplus II: http://www.newegg.com/Product/Product.a ... 6811112066

Both use an inverted motherboard with left-side access. There is some debate about whether motherboard mounted heat pipes work well in this orientation. I'm willing to do the work (but not pay Lian Li's prices).

Cheers, and happy modding !

Thanks!