[noggin]

What about in terms of HTPC..
what is the lowest CPU do you recommend that can do this?

Also is there any second hand dell or lenova SFF PCs etc that can do this? 

I like to consider all options... 

A lot of people have switched from Intel/AMD HTPCs to ARM-based boxes because HDR support, and reliable HD Audio (which for years was a given), become a major issue with Intel/AMD/nVIdia PC solutions. Quite a few of the former Intel/AMD platform Kodi developers have either retired from active development or switched their interest to ARM platforms.

There is some HDR support now - but because Intel took forever to implement HDMI 2.0 native support on their SoCs (they relied on a Displayport to HDMI solution using an LSPCon to convert between the two standards, which itself needs firmware updates quite often) the conversion often caused issues with HD Audio bitstreaming and HDR support. Driver support in Linux vs Windows was also an issue. (Some things work better in one OS than the other)

Make sure you check out HDR and HD Audio support specific to the box you are buying AND the OS you will be running.

One major reason for the Intel/AMD -> ARM switch for many is that the ARM SoCs are developed specifically for the Media Player market - so support for Media player functionality (HDMI 2.0, HDR, HD Audio etc.) is their prime focus, whereas for Intel and AMD, it's far less of a priority compared to laptop and desktop day-to-day computing functionality, so their focus is less specific (and development of new functionality seems to lag)

I'm not saying HTPCs are bad - but they are no longer as dominant as they were 10-15 years ago.

[madmax2]

What about in terms of HTPC..
what is the lowest CPU do you recommend that can do this?

Also is there any second hand dell or lenova SFF PCs etc that can do this? 

I like to consider all options... 

A lot of people have switched from Intel/AMD HTPCs to ARM-based boxes because HDR support, and reliable HD Audio (which for years was a given), become a major issue with Intel/AMD/nVIdia PC solutions. Quite a few of the former Intel/AMD platform Kodi developers have either retired from active development or switched their interest to ARM platforms.

There is some HDR support now - but because Intel took forever to implement HDMI 2.0 native support on their SoCs (they relied on a Displayport to HDMI solution using an LSPCon to convert between the two standards, which itself needs firmware updates quite often) the conversion often caused issues with HD Audio bitstreaming and HDR support. Driver support in Linux vs Windows was also an issue. (Some things work better in one OS than the other)

Make sure you check out HDR and HD Audio support specific to the box you are buying AND the OS you will be running.

One major reason for the Intel/AMD -> ARM switch for many is that the ARM SoCs are developed specifically for the Media Player market - so support for Media player functionality (HDMI 2.0, HDR, HD Audio etc.) is their prime focus, whereas for Intel and AMD, it's far less of a priority compared to laptop and desktop day-to-day computing functionality, so their focus is less specific (and development of new functionality seems to lag)

I'm not saying HTPCs are bad - but they are no longer as dominant as they were 10-15 years ago.  

So you saying something Ryzen or latest intel CPU can't playback HDR smoothly?

but if we get a nvidia or AMD gpu it wouldn't be an issue..
even if we got a slower intel cpu e.g. i5 4750 (from DELL 9020 SFF PC)

what is the your recommendation of the arm media player to get right now?
is it odroid N2?

[madmax2]

The most powerful ones we are talking about are devices like the HardKernel ODROID N2 & Ugoos AM6 - both have S922X AMLogic chipsets in them.
If you wanted to - there is enough raw CPU grunt under the 6 Core CPU hood that you can Software decode 1080p anything. That's Intel i series NUC territory.

Then there is also the cheaper S905X3 chipset - ODROID C4 and the Ugoos X3 Cube, which are still very capable.

I mention those Brand names because they have the same high quality hardware componentry in every device, not some generic components throw together in what turned out to be cheapest available for the specific production run available in Shenzhen China at the time.

Plus you will get properly designed & tested passive thermal cooling solutions, that will be reliable long term.

All of those have Gigabit LAN, essential for home network 4K HDR Bluray Rip streaming.

The reason why we are banging on about these new AMLogic chipset devices, running CoreELEC Kodi (click) is because:

a) The provide great bang for the buck for 4K HDR + HD audio Kodi usage - and are pretty damn snappy as well for the price paid.
b) Firmware and Software support from the CoreELEC guys is great, you even get auto OTA updates.
c) The AML / CE Kodi combo is reliable and it just works. Hardware decoding virtually anything you want to throw at it. Set and Forget.
d) HDMI CEC control that is also highly configurable from within Kodi.
e) CE Kodi is optimised to run Kodi as fast, smooth and stable as possible. You also get extra custom Kodi features added.

Yes virtually all stuff, but it has a 2015 era 4 Core CPU package (other 4 cores disabled), so any tricky stuff that needs Software decoding may not work that well.
There is no HDR10+ support or VP9p2 hardware decoding possible at all.
With the Shield you are also dealing with Google Android OS updates, which with each OS Bump - seems to not go that smoothly.

The Shield is a bit of a jack of all trades media player, but master of none. Android Fanboys love them, but there are some rough edges that annoy the hell out of users.
CoreELEC Kodi can be thought of as a scalpel, designed from the ground up to run Kodi as fast, smooth and stable as possible.

It really depends on what you actually need personally and how demanding a user you are. 

What about in terms of HTPC..
what is the lowest CPU do you recommend that can do this?

Also is there any second hand dell or lenova SFF PCs etc that can do this? 

I like to consider all options... 

From the - 4K HDR10 - State of Play thread - important media player limitations - sticky at the top of the forum... follow the links...

That is where all the HDR info resides...

Intel x86_64
NEW - 4K HDR support Now available with Windows and Kodi v19 using THIS ongoing development build (click) & there is also another - independant - Kodi Matrix 19.0 HDR Windows API build available HERE (click) 

What is your recommendation as the best media player ranking from 1 to 3 or 1 to 5 etc..
Is Odroid N2 = 1 (the most recommended)?

How is the quality of the boards?
the 4 weeks warranty on their site is pretty crap but it is the only option if we want to buy the EMMC + 4G CE edition of the N2
which is cheaper than locally (especially for the 16GB EMMC price) and you can't buy the CE edition locally right now...