HTPC: Can an I5 3rd gen process 4k@120?

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Rev. Night

[H]ard|Gawd
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So i have my older HTPC and my much new gaming PC. As per my usual process, when the gaming PC gets upgraded, the parts go into the HTPC, and then those oldest parts gets sold. I will be buying a 4k@120, HDR10+ tv soon, so I want to make sure the HTPC is up to snuff.

Relatedly, I've read that the Radeon 480x, via DP 1.2 cables, can do 4k@120 and 10bit color (HDR, HDR10, HDR10+). A good sanity check goes a long way though.

Edit:
For clarity, this HTPC will not be playing 3d games other than basic family friendly games. It will be used entirely for streaming Amazon, Netflix, Hulu, reddit football (albeit these streams aren't in 4k), and other Win 10 browsing.

I want to make sure that the parts below, via DP1.2 or HDMI 2, can run streamed content at full 4K, HDR10+, 120hz, etc.


Parts:
CPU: i5 3550p. Stock is 4x3.3gz, but I overclocked it to be a 2x3.7ghz. Runs games better as a dual core, higher clocked
GPU: Amd Radeon 480x
Cableing: DisplayPort 1.2 preferably.

Thanks!
 
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If you want to drive an HDMI 2.1 port on your new shiny TV, you're going to need at least DP v1.4, and you'll have to wait for them to develop the adapter (it took them about six months after the Fury X was released to get DP 1.2 to HDMI 2).

So you will be waiting awhile for something to drive it at native resolution. But for now you can just use the HDMI 2 port on your RX 480.

As long as you're only playing marginally-challenging games, and have at least the RX 480, you should be able to play at native resolution at med setting at at 45-60 fps. But upscaling from 1440p is a popular option on these new TVs, the that card can handle most games at 1440p high.

But turning on HDR in new AAA titles will bring that card's performance down to only 1080p, so be aware of this. HDR typically cuts performance by about 25%.

But if you want 120 hz native resolution, you're going to have to wait for the next round of cards anyway. You might as well wait until there's a native hdmi 2.1 port on them.
 
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Gents,

Thanks for your quick responses. I edited the OP to reflect that this HTPC, with the parts provided, will just be for streaming 4k content from various providers. Few 3d games will be played.

"
Edit:
For clarity, this HTPC will not be playing 3d games other than basic family friendly games. It will be used entirely for streaming Amazon, Netflix, Hulu, reddit football (albeit these streams aren't in 4k), and other Win 10 browsing.

I want to make sure that the parts below, via DP1.2 or HDMI 2, can run streamed content at full 4K, HDR10+, 120hz, etc."
 
Okay, if all you care about is streaming video, 60hz will be plenty. And your current card can handle decoding HEVC 4k. But be aware the card has no hardware support for VP9 (used by Youtube in some 4k and 8k streams, depending on browser), but the hybrid decoder should be fine.

There are no TVs with DisplayPort, so until we see DisplayPort 1.4 to HDMI 2.1 converters, you'll be limited to running either 4k 8-bit @ 60 hz 4:4:4, or 4k 10-bit @ 60hz 4:2:2.

Get used to switching between modes, unless you don't mind the color issues in other non-HDR applications. There's also a loss in text sharpness going from 4:4:4 down to 4:2:2, but you tend to only notice it on the largest displays.

I assume you'll also be using this for web browsing? You''ll have to set the Windows font scaling to something like 300%, and then set a minimum font size on your web browser (it will break some sites, but the vast majority will still behave).

Casual games will have no trouble on an RX 480 playing 4k at 60 hz. You might even be able to hit 120hz on some of the easier ones.
 
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Excellent! I'll have to do some research about how to switch between the 4:4:4 modes and 4:2:2

Also, the gpu I currently have in the HTPC is a AMD Radeon 280x. According to its AMD product page, it can do 4k60 streaming, but what about HDR? HDR10+? Is all of that handled on the software side? Again, for streaming and windows browsing only, will there be a performance lift moving from the 280 to the 480?

edit: While 280x can do 4k, according to this article from Rock, Paper, Shotgun, they can't do HDR. So it looks like the orginial plan is still a go: Upgrade to Vega, move 480 to HTPC, buy 4K HDR10+ tv

HDR: AMD graphics cards
For those on the AMD side of the fence, you’re looking mainly at their Polaris family of GPUs – that is, the RX 400 and RX 500 series – as well as their high-end Vega graphics cards. You can also expect AMD’s Navi graphics cards to support HDR whenever they eventually come out, as well as their very soon-to-be released Radeon 7.

However, if you happen to have one of AMD’s older R9 300 series cards, you may well be in luck, as these also support HDR over their HDMI 1.4b and DisplayPort 1.2 outputs, albeit with a few limitations – namely, they can only reach a maximum of 30fps at 4K and a colour depth of 8-bits rather than 10-bits when connected over HDMI due to bandwidth limitations.

HDMI 1.4b and DisplayPort
AMD Radeon R9 380
AMD Radeon R9 380X
AMD Radeon R9 390
AMD Radeon R9 390X

1.2 HDMI 2.0 and DisplayPort 1.4
AMD Radeon RX 460
AMD Radeon RX 470
AMD Radeon RX 480
AMD Radeon RX 550
AMD Radeon RX 560
AMD Radeon RX 570
AMD Radeon RX 580
AMD Radeon RX Vega 56
AMD Radeon RX Vega 64
 
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Rev. Night said:
Excellent! I'll have to do some research about how to switch between the 4:4:4 modes and 4:2:2
Click to expand...

It's as simple as turning on and off HDR under the Settings menu.

Windows will automatically negotiate the best it can manage, based on the cable quality and the port capability. Bit that can lead to some unforeseen issues, if Windows just decides it doesn't like the cable.

That means 4k @ 60hz 8-bit 4:4:4 (HDR off) or 4k @ 60hz 10-bit 4:2:2 (HDR on)
 
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