I have gradually upgraded my first custom build but decided to finally move it from its old, closed black box to a new, fancy case with proper(ish) cable management on occasion of the GTX 1080 upgrade. I'm quite happy with how it turned out!
Motherboard, RAM, the 840 EVO and both HDDs were re-used from my 2013 build (i5 4570 / AMD 7870). Upgraded to a GTX 970 and 4790k alongside with a NH-D14 in 2014. New EVGA PSU was purchased in 2015 after the same PoS bequiet model broke twice within two years (will never buy from them ever again... such a headache).
2016 update included a clean install of Windows 10 Pro on a new 850 EVO 500GB as primary system SSD, moving the build to the Corsair 400C, replacing the CPU and case fans with the sexy black Noctua Industrials and of course retiring the 970 and moving on to the EVGA GTX 1080 FTW. Also did some custom cable sleeving for the SATA and 3pin fan cables and ordered a cable kit for the PSU and MB to fit the color scheme.
I edit and render videos on a regular basis, so the 4790k (overclocked to 4,5GHz @ 1,2v) and 16GB of RAM definitely come in handy and aren't overkill in the slightest as some people will usually try to tell you. It does also very well for the occasional livestream and generally doesn't struggle with anything I throw at it. Been eyeing to upgrade to a 6+ core CPU but currently I can't really justify the cost (new MB, RAM, expensive CPU... nah).
Since I'm gaming on a 2560x1440 144hz Gsync-Monitor, the GTX 1080 was certainly the card to go for. My 970 did okay (1080p monitor broke a few months after I got the card) but an upgrade definitely was in order as it struggled to provide a smooth experience with the latest games at native resolution and appealing settings.
Temps & Noise
All Noctua fans have been given the "chromax" treatment to fit my desired color scheme. Case fans have been mounted using their anti-vibration rubbers. The PC is basically inaudible during idle (fans set to ~500rpm until 50°C) with turned off HDDs (as soon as 1TB SSD prices drop to a reasonable level I'll kiss these noisy ******* goodbye haha!). CPU idle temp is around 20 delta room temp, GPU quite a bit more (~30-35 delta) since it doesn't clock down lower than 721mhz core clock. PSU provides a fanless mode and GPU fans do not turn on until it hits about 60°C so it's a wonderfully silent build for office stuff, browsing and watching Netflix/YT!
During heavy load and gaming the noise level obviously rises considerably but not to a degree to where I feel annoyed while wearing headphones. I set a temp target for both, the CPU (65°C) and the GPU (75°C) so the fans will ramp up on their own. I've got to say the fan noise characteristics of the Notua and ACX 3.0 fans are pretty sweet as well: couldn't spot any clicking, revving or other annoying sounds.
Building in the 400C will all my drives was a bit stressful since it doesn't really provide much room at the back for managing all the cables. It feels like Corsair should've increased the size by 2 or 3 cm on each dimension of the case. But that being said, it's cool that you can force the back cover to close even with a lot of cabling overhead. Probably not healthy for the back panel but it works :)
I'm also not completly happy with how the look of the individually sleeved cables turned out but I'll leave it at that for the time being.