Mac mini driving two LG UltraFine (5K) Display thunderbolt displays?

[xoanohn]

The tech page for the new mini says that "
Simultaneously supports up to two displays: One display with up to 6K resolution at 60Hz connected via Thunderbolt and one display with up to 4K resolution at 60Hz connected via HDMI 2.0

Would it be able to drive two LG UltraFine (5K) Display thunderbolt displays?

 

[MisterAndrew]

That's a good question. It looks like you could run one at full resolution over Thunderbolt and one at 4K resolution over HDMI.

 

[xoanohn]

That's a good question. It looks like you could run one at full resolution over Thunderbolt and one at 4K resolution over HDMI.

The problem is these monitors only have thunderbolts.

 

[Deinocheirus]

This is so frustrating. What I really want is a 48" 8K display from Apple with Apple display quality.

Nothing fits my needs. Multiple displays don't cut it unless you have at 3 (left, center, right) and nothing can drive 3 displays smoothly without help.

Even if I wanted to plunk down $5000 for Apple's best...its a 30" 6K display. Too big in the wrong direction. Elements too small.

Why am I so at odds with the entire display market?

 

[LonestarOne]

The tech page for the new mini says that "
Simultaneously supports up to two displays: One display with up to 6K resolution at 60Hz connected via Thunderbolt and one display with up to 4K resolution at 60Hz connected via HDMI 2.0

Would it be able to drive two LG UltraFine (5K) Display thunderbolt displays?

5 is greater than 4, so, no.

 

[saulinpa]

I'm wondering if you can only have one display on the TB bus.

 

[MyopicPaideia]

I'm wondering if you can only have one display on the TB bus.

According to the Apple tech specs, yup. Looks choked there.

 

[Deinocheirus]

I'm wondering if you can only have one display on the TB bus.

The previous mini could run 3 4K displays, 2 off of TB and 1 off of HDMI. Depending on who you ask, it worked OK.

Why would this be such a step backward when graphics performance is allegedly so much better?

 

[Boil]

The tech page for the new mini says that "
Simultaneously supports up to two displays: One display with up to 6K resolution at 60Hz connected via Thunderbolt and one display with up to 4K resolution at 60Hz connected via HDMI 2.0

Would it be able to drive two LG UltraFine (5K) Display thunderbolt displays?

5 is greater than 4, so, no.

Well, if you put a 5K display on the 6K TB port, and a 5K display on the 4K HDMI port, won't they just even out...?!? ;^p

According to the Apple tech specs, yup. Looks choked there.

I wonder how having the Apple 6K on one TB port will affect anything on the other TB port, like an external RAID...?

 

[MyopicPaideia]

I wonder how having the Apple 6K on one TB port will affect anything on the other TB port, like an external RAID...?

Good question and relevant to me because I run a TB2 Lacie 4Big RAID right now.

 

[saulinpa]

The previous mini could run 3 4K displays, 2 off of TB and 1 off of HDMI. Depending on who you ask, it worked OK.

Why would this be such a step backward when graphics performance is allegedly so much better?

It's not performance, but design. Most require a separate video (DP?) controller for each monitor stream and they may have run out of space on the die.

 

[MisterAndrew]

The problem is these monitors only have thunderbolts.

Oh, I'm sorry. I suppose you would need to get two 4K displays, or a 6K plus a 4K. The higher end model that will replace the Intel model might support two 6K Thunderbolt displays. Perhaps it's best to wait.

 

[joevt]

From the tech specs, it seems we can conclude that the Thunderbolt controller has only one DisplayPort input supporting DisplayPort 1.4 with Display Stream Compression.

Therefore, it cannot support the LG UltraFine 5K at 5K because that requires two DisplayPort connections.

Which means zero is the number of LG UltraFine 5K displays this supports.


Alternative interpretation:

The 6K display is using dual DisplayPort HBR3 connections (not DSC).
Which means
- the mini can support one LG UltraFine 5K display and a 4K display.
- the mini can support three 4K displays.


In either case, we can safely conclude that Apple sucks at tech specs.

 

[joevt]

I wonder how having the Apple 6K on one TB port will affect anything on the other TB port, like an external RAID...?

A display on one port does not affect bandwidth of PCIe data on the other port. That's because DisplayPort is a separate input to the Thunderbolt controller. Both ports can do 40 Gbps but that requires both PCIe (maxes out at ~ 22 Gbps = 2750 MB/s over a Thunderbolt port) and DisplayPort data to be mixed together. A discrete Thunderbolt controller is limited to 31.5 Gbps of PCIe data total for both ports because they use a PCIe 3.0 x4 connection. An integrated Thunderbolt controller like in the Ice Lake or Tiger Lake CPUs doesn't have that limit (in that case it's like 5 GB/s shared by all four ports). M1 also has integrated Thunderbolt (but only supports two ports).

It's currently impossible to fill the bandwidth of two Thunderbolt ports (40 Gbps each) of a discrete Thunderbolt controller. you could fill one port with a 6K display (dual HBR3 36 Gbps) plus 22 Gbps of data on the other port ~ 60 Gbps total. An integrated Thunderbolt controller has similar limits (for two or four ports).

I wonder why they didn't give the M1 four ports? Because USB4/Thunderbolt 4 has hubs with multiple downstream ports?

 

[saulinpa]

Apple's LG 5K page now shows compatibility with the M1s. So means TB does have access to 2 DP streams so should support 2 TB attached 4k monitors.

Update: Real world tests seem to be that 2 TB attached 4k monitors don't work.

 

[joevt]

Apple's LG 5K page now shows compatibility with the M1s. So means TB does have access to 2 DP streams so should support 2 TB attached 4k monitors.

Not seeing it. Need a link for that. Nevermind. Need to click the + button next to Compatibility.

Compatibility just means the display will do something. I think in this case it will just do 4K (iPad Pro and MacBook are also limited to 4K - see https://support.apple.com/en-us/HT210205 ).

 

[saulinpa]

Not seeing it. Need a link for that. Nevermind. Need to click the + button next to Compatibility.

Compatibility just means the display will do something. I think in this case it will just do 4K (iPad Pro and MacBook are also limited to 4K - see https://support.apple.com/en-us/HT210205 ).

Possibly. That page hasn't been updated for the M1s though.

 

[xoanohn]

Apple's LG 5K page now shows compatibility with the M1s. So means TB does have access to 2 DP streams so should support 2 TB attached 4k monitors

does this mean the 5k LG connected to TB will down res to 4k?

 

[saulinpa]

does this mean the 5k LG connected to TB will down res to 4k?

It does with the TB3 to TB2 adapter. We don't know yet how the M1 will work.

 

[dogslobber]

I doubt DisplayLink will work anymore either.

 

[ght56]

I wonder why they didn't give the M1 four ports? Because USB4/Thunderbolt 4 has hubs with multiple downstream ports?

My best guess would be maintaining differentiation between a two-tier product lineup (in the future.) They are able to tier the MacBook Air with two different GPU core counts (in addition to storage). The two versus potential future four port model MacBook Pros could be a partial or sole differentiator between a lower and higher tier MacBook Pro 13. If a later four port (M1/M1 derivative) also added the ability to operate more than one external plus perhaps a higher RAM option, that would further differentiate low tier and high tier 13-inch MacBook Pro configurations.

Simultaneously, over the next few years I expect we will begin to see USB 4 hubs with the capability of today's Thunderbolt 3 hubs at vastly lower prices. Apple's vision for a one port does all solution has always been hampered to some extent by USB's limited IO and Thunderbolt 3's high price. Six years after the first USB-C Macs debuted, this idea might really begin to come of age?

 

[turbineseaplane]

This was such a great opportunity to introduce a new standalone Apple display for the masses…

I’m really disappointed they have done nothing in the VAST range below the XDR

 

[MyopicPaideia]

This was such a great opportunity to introduce a new standalone Apple display for the masses…

I’m really disappointed they have done nothing in the VAST range below the XDR

Agreed - A 4K slightly paired down version would have been awesome to have...

 

[ght56]

This was such a great opportunity to introduce a new standalone Apple display for the masses…

I’m really disappointed they have done nothing in the VAST range below the XDR

As am I. It kind of leads me to believe that this might not be a very profitable endeavor for Apple, or that us forumites want an Apple display much more than other Apple users. They also might not want to deal with servicing displays?

 

[turbineseaplane]

As am I. It kind of leads me to believe that this might not be a very profitable endeavor for Apple, or that us forumites want an Apple display much more than other Apple users. They also might not want to deal with servicing displays?

All are possible…

But at the end of the day, it’s just mind blowing to me they are OK with people hooking up their beautifully designed computers to the range of “ugh” displays one can find in any random tech store.

One would think, in this new single cable USb-C future, Apple would have been all over making an unbelievably gorgeous monitor docking situation with just one single cable needed.