Passive Mini-ITX Strix380 4790K

[useful_idiot]

It has taken me over 1 year to fully develop this system.

General Characteristics: This system is silent while doing day to day office tasks, i.e. word processing, music, pdf's, web surfing(all at the same time). It can can handle anything you throw at it and none of the fans will turn on. What will cause the Strix fans to fire up is when I start Unigine Heaven for benching or some Steam game for just a few minutes. The heat profile of the machine is LARGELY due to the case only being only adequate for passive cooling. There is much Fractal could do to optimize this case for passive cooling and I hope one of their engineers gets in touch with me so I can tell them where the case needs improvements for convection cooling. With that said, the temps at day to day activity generally stay at around 50C +/- 5C. When gaming the temps will rise to a steady 70C and stay there for hours on end with no issues. The case could perform much better with just a few tweaks so hopefully Fractal contacts me or if not I will find a nice machine shop locally to do the work.

"Dude it cant be silent...nothings silent": Yes Spicoli, you are correct. To get to the technical aspects of silence. I was running a Scythe Gentle Typhoon 500rpm fan on a previous iteration of this system and its rated at 5db. It was so quiet that no quiet obsessed person could ever complain about it being the only fan in their system. I highly recommend that fan if you must run a fan, however my system with no fans running is about as loud as a monitor. Thats right, id say it's about 2.5db's. I hear some electrical hum when i place my ear up to the vents in the case when its on. Thats all, just a happy little hum from 1 inch away but from where I sit, I cant hear a F'n thing.

Critical components list.
i7-4790K Processor
ASUS Z97I-PLUS System Board
CPU Cooler Zalman FX100
Corsair AX860, NOT i series!!
ASUS STRIX R9 380
Fractal Core 500 case

[quest_for_silence]

If you love it, well done.

Just out of curiosity: what about the CPU temp when stressed (those things like OCCT, Prime95, LinX)? Can the Zalman cope with that? I think no, but I'd like to know the real figures, if any.

[NeilBlanchard]

My question is about the components in the optical bay - is that a optical drive and a something else below it? Is it a memory card reader?

[useful_idiot]

If you love it, well done.
Just out of curiosity: what about the CPU temp when stressed (those things like OCCT, Prime95, LinX)? Can the Zalman cope with that? I think no, but I'd like to know the real figures, if any.

I run 1 round of Unigine Heaven as a "can it handle it" bench and CPU temps top out at around 90C with the cover on. The problem with passive cooling and benching is all that hot air cant escape fast enough through convection alone. I really wouldnt bench a passive system for longer than 15 minutes without taking the cover off. The good news is that nothing I do in the real world comes close to pushing these components to Tmax.

My question is about the components in the optical bay - is that a optical drive and a something else below it? Is it a memory card reader?

Good eye! It's a 3.5 inch HDD bay, I use a M.2 drive that attaches to the bottom of my system board so that 3.5 inch bay was used very strategically for cable management. If you go to the website for the case you can see an exploded view of that piece.

[quest_for_silence]

I run 1 round of Unigine Heaven as a "can it handle it" bench and CPU temps top out at around 90C with the cover on. The problem with passive cooling and benching is all that hot air cant escape fast enough through convection alone. I really wouldnt bench a passive system for longer than 15 minutes without taking the cover off. The good news is that nothing I do in the real world comes close to pushing these components to Tmax.

Thanks!

BTW, IMVHO a Noctua R8 Redux PWM inside that FX100 could be a nice addition.

[edh]

IMVHO a Noctua R8 Redux PWM inside that FX100 could be a nice addition.

Agreed. When a passive cooler is hitting 90C even the slowest spinning fan will yield enormous cooling improvements. Buzzing components are typically louder than a good fan doing 200-300rpm and the massive reduction in temperatures will have a knockon effect on the PSU and graphics card, keeping their fans stopped for longer.

[quest_for_silence]

a Noctua R8 Redux PWM

s/R8/B9

[useful_idiot]

No need for a fan guys, building a great bencher was never my intention. My real world gaming temps are 70C.

[quest_for_silence]

No need for a fan guys, building a great bencher was never my intention. My real world gaming temps are 70C.

Obviously it's up to your call, do what you think best (though there is a chance that you're slowly cooking any surrounding part).

I just leave you with a question, but for yourself only, as I don't need/want to get any answer or comment: whether your GPU and PSU do start their fans when the relevant temps are 70°C, why your CPU should not do the same?

Thanks again for sharing your build and enjoy it!

[useful_idiot]

Almost 1 year since initial post and I still enjoy the silence everyday!

Updates
Upgraded to 16GB Ram, Crucial Ballistix.
Original ASUS mini pci wireless card died and was replaced with Intel 7260. Very nice card!
Samsung M.2 850 Evo 128GB was upgraded to Samsung M.2 960 Evo 256GB, only running at X2 speeds but noticeably faster than the 850 EVO and buttery smooth.
Everything else is exactly the same.

I have decided not to upgrade to 7700K. I am coming up on 3 years with Devils Canyon (4790K) soon and the only reason I have to upgrade is M.2 X4 support which does not bother me anymore after upgrading to the 960 Evo.

On a final note I hope anyone who found my blueprints useful and built their own passive PC sign up for this site, post some pics of their rig in a new thread all your own, and give me a shoutout!

[jung]

Cool one! But what I have to say is that I really like your username lol

[useful_idiot]

I'm wrapping up testing of this system.


I will be upgrading to the next gen Intel proc when they are released around Oct. I wont be posting my new rig here because it will be a clone of what I have accomplished with this build. I have added a single exhaust fan due to 90% cpu loads from lots of multi-hour video processing. Someday I will do a write up of my fan testing in the fan section where it belongs. I have really enjoyed this system for many years and I hope I was able to help a few people in the process.

Essentials of what I did to build a really quiet PC
-fanless cpu cooler
-video card with fans that are off at idle
-power supply with fan that is off at idle
-single "top of case" exhaust fan with fan controller

[Japanese Capacitor]

Nice build in it's times it was, but with upcoming one don't bother too much with passive and semi-passive components. Things moved forward to the point, where active cooling is able to be the same silent as passive, but do much better thermally. Decent PSUs (far from high-end as Corsair AX) are unhearable below at least 50% load of wattage, so semi-passive mode is gimmick. Decent case fans are able to go way below border of them being inaudible. All what matters nowadays are beefiest possible and active CPU and GPU coolers as they noticeably determine the result.