55X8005C (X80C) - 4k@60hz, 1080p@120hz and HDR questions

[Bilazaurus]

Hi,

I have bought 55X8005C which is X80C series. I have several questions to which I cannot find solid answers

1. I cannot display 4k resolution at 60hz with my PC. It just says "no signal" but it displays 4k@30hz. What is the max HDMI cable lenght to provide enough bandwidth? I have a 5 meter HDMI cable rated, presumably, HDMI 2.0. Is the cable poor quality or what? I have a top-end graphic card - GTX980Ti so I don't think GPU is the problem.

2. Can X80C display 1080p in 120hz? I want to play older games at 1080p with 120fps running from my PC. Is 120hz REAL in this TV? Is it possible to achieve real 120FPS?

3. I've seen that X810C which is USA version of X8005C received an firmware update introducing HDR but I cannot see that in European firmware changelog. Will X8005C get HDR?

[xx4L0Mxx]

Hi. I have the KDX8509c, but hopefully this may help. 

HDMI cable HAS to be certified for HDMI 2.0 18gb/s for 2160p@60hz. I use a 3m cable and it works perfectly from 2xMSI 970gtx in sli. Someone on here tried a 10m cable that wouldn't output properly, 5m MAY be OK. 

Have you pressed home button-settings-external inputs and selected HDMI 4k output to enhanced on HDMI 1? I have my pc through HDMI 1, you have to enable enhanced mode to be able to get 2160p@60hz 4:4:4 rgb chroma, otherwise you can still output 2160p@60hz, but you are limited to 4:2:0.

I tried 2 different HDMI 2.0 cables and one works perfectly but the other is hit and miss, I'm on my phone at the minute, but I will post a link to the cable I use here later. 

As to the 120hz question, your TV needs to have active 3d,this will mean your panel is 120hz. Mine is, and I just make a custom resolution in nvidia control panel 1080p@120hz and can happily play project cars at 1080p@120fps.

[Anonymous]

To add to the post from xx4LOMxx 

In regards to HDR, this has been enabled in the UK/EU for a while now

[Bilazaurus]

Thank you for your input I'm glad they introduced HDR but in reality we probably won't be seeing much HDR material in some time.

Concerning enhanced hdmi setting. Yes, I have it on. I blamed my TV and/or PC and windows 10 for not running 4k@120hz. Then it hit me and I switched to 4k@24hz and voila! It displays. It got me thinking that it may be a cable. I didn't use a cheapo cable, 20$ for 5m hdmi is not the best but also not the worst (keeping in mind that cables are a scammy business). I'd be glad if you give me a model of your cable that worked thought I guess they won't be available in Poland

[xx4L0Mxx]

Hi. I use the 3m pro gold version. It has worked perfectly for me. I did have a couple of problems with the last nvidia driver, but the latest whql drivers dated 15 Feb work perfectly again. 

Cable :

http://www.amazon.co.uk/gp/aw/d/B0031APPM4/ref=mp_s_a_1_1?qid=1455963413&sr=8-1&pi=SY200_QL40&keywor...

[Bilazaurus]

As I suspected It was the cable. I've tested 4 cables. My old one (no), cheap one 4m (no), middle-priced (no), high prices (~40$) and it worked.

Do you know if I can get 12bpc colors with 4k@60hz 4:4:4?

[xx4L0Mxx]

No you can't. You can get either 2160p@60hz ycbcr 4:2:0 12 bit colour or 2160p 4:4:4 RGB Full 8 bit. 

They both look good, but I think RGB 8 bit is far superior colour wise and is noticeably better. 

The only game on the market that supports greater than 8 bit colour is Alien Isolation as far as I'm aware anyway. 

[Bilazaurus]

I've gotta problem. I put custom resolution in Nvidia settings (1080p/119hz) and it only shows 1/4 of image, distorted. Any clue?

[Bilazaurus]

I've got 120hz sorted out but I believe you don't realise it doesn't really work. I've noticed almost no improvement. And to back it up, I used a frame skipping test. And unfortunately it confirmed my fears - this TV skips every second frame so this "120hz" is useless.

[xx4L0Mxx]

You can't have set things up correctly, do you have hardware acceleration enabled or disabled in your browser settings?

Do you have v-sync enabled or disabled in your Nvidia Control Panel settings?

My results :

Refresh Rate Test :

Frame Skip Test :

Project Cars In-Game settings & Fraps and MSI Afterburner OSD Framerate :

Project Cars In Game 1920x1080@120 HZ V-SYNC ON - Fraps & MSI Afterburner OSD :