Quote from: Danielius on March 17, 2021, 13:45:27
But as I understand Thunderbolt port here is only used for charging and most articles I saw says that thunderbolt cannot be split into multiple thunderbolts over a hub? Thus, there is kind of no way for me to add an external GPU over thunderbolt for example? Only when I am on battery in that case?

That was true of Thunderbolt 3 I think. Thunderbolt 4 does allow use of a hub connected to a single port to convert it into multiple TB4 ports. (https://betanews.com/2020/10/01/owc-thunderbolt-4-hub-tb4/)

However the 40 Gbps bandwidth (actually 32 Gbps only for data) will obviously be split if you use all connected devices at the same time.

This laptop would have been ideal with at least one more Type-C port instead of the lone Type-C+TB port. Like the ThinkPad L14/L15 model has.

But as I understand Thunderbolt port here is only used for charging and most articles I saw says that thunderbolt cannot be split into multiple thunderbolts over a hub? Thus, there is kind of no way for me to add an external GPU over thunderbolt for example? Only when I am on battery in that case?

Quote from: xpclient on January 25, 2021, 18:39:20
So a Thunderbolt 3 SSD like Samsung X5 which is connected to an x4 PCIe link TB3 port in my high-end gaming laptop will probably not see any further improved performance for a TB4 port?

Oh, one last thing. I would normally assume the SSD has to be TB4 to see improvement. You've got backward compatibility - if you connect TB3 device, the port should behave like a TB3 (and that should mean TB3 bandwidth limits). Also, the TB3 controller inside that device might not know what to do with the extra bandwidth. But this is really a negotiation thing (it's a soft limit, not hard limit). If you've got x4 on both ends, there is no reason why TB3 couldn't support 32 Gb/s. The controller just doesn't want to. If you're seeing significant improvements with eGPUs, perhaps it works.

I wrote that the reservation doesn't bother you. I should have written that it doesn't bother you as much. Because there is also USB besides PCIe. There is no doubt that TB4 is more flexible and the more ambitious minimum specification is certainly welcome. Still, I wish TB4 offered 80 Gb/s (full-duplex) and continued the tradition of doubling. Although, I can understand that it might be difficult to do it without a new connector. And that it would probably be significantly more expensive. Still, with resolutions going up, refresh rates going up, 40 Gb/s doesn't leave much room.

Quote from: xpclient on January 25, 2021, 18:39:20
Ah that is very useful, interesting, important and rare info that clears my confusion. Thank you for explaining the differences between DisplayPort in TB and in USB-C Alternate Mode.

Wikipedia does mention this too but in the USB-C article: "All Thunderbolt 3 controllers both support Thunderbolt Alternate Mode and DisplayPort Alternate Mode. Because Thunderbolt can encapsulate DisplayPort data, every Thunderbolt controller can either output DisplayPort signals directly over DisplayPort Alternative Mode or encapsulated within Thunderbolt in Thunderbolt Alternate Mode. Low cost peripherals mostly connect via DisplayPort Alternate Mode while some docking stations tunnel DisplayPort over Thunderbolt."

So a Thunderbolt 3 SSD like Samsung X5 which is connected to an x4 PCIe link TB3 port in my high-end gaming laptop will probably not see any further improved performance for a TB4 port?

I would like to add that USB4 also supports tunneling. You can tunnel simultaneously USB 3.2 and DP 1.4a irrespective of Thunderbolt support (TB support adds PCIe tunneling and is optional).

Alternate modes really relate to the port itself - USB-C. They essentially dictate how it's wired up, what the pins do. In DP mode, the port becomes a weirdly shaped DP. All the high-speed serial lanes of USB-C port will be video out (at least in the case of 2.0; but in all cases, the port will be DP-only) and it should behave like a DP on a GPU. In a TB mode, half the links are used for receiving like it's with USB (you've got 40+40 instead of 80+0), you've got full-duplex communication and it should behave like a TB port. TB itself does support carriage of DP. Because TB was designed to offer an all-in-one solution (power + data + video) so that you can have just one cable for everything. And now, as I already wrote, USB4 joins the fun with TB-like DP tunneling. You can imagine it like switching between GPU, TB controller, USB controller. In reality, there should be just one controller behind the port (either USB or TB) which is connected to all the different "resources" and which does the switching internally (it's responsible for the detection, negotiation and reconfiguration).

Actually, SSD permitting, you should see an improvement in write speeds. As long as there is no high resolution or very high refresh rate display daisy chained on the same port (3840x2160 @ 60 Hz with 24 bit colour depth takes, I believe, almost 13 Gb/s). Exactly because of the change in how much bandwidth is reserved for DP. I believe TB3 reserves 18 Gb/s for DP - insane if you ask me. Leaving at most 22 Gb/s for data, even with four links of PCIe. In TB4, you get the full 32 Gb/s. I believe this is the main reason why you see a significant improvement with eGPUs. In this respect, I have poorly worded my previous post. In the cut-down x2 implementations, you've got so much headroom that the DP reservation doesn't bother you. But in the full x4 implementations, you only really get x2.75 because of the reservation. As I wrote, the difference is small in mixed scenarios, at least with higher resolutions (see above). And even in data-only, it's fairly specific - like eGPU, like really fast SSDs. And of course, it's easier to hit the limit if you daisy chain.

It's not Golden Cove.
It's Willow Cove.

Quote from: _MT_ on January 25, 2021, 12:08:56
When you send video + data, you're not using DP Alt mode. That's a USB thing, for one. And it's used when you're sending exclusively video. That's why DP 2.0 can achieve 80 Gb/s in Alt mode using the same technology - video is unidirectional, they can use all links for transmitting. In mixed traffic, you're using tunneling and you have 40 out/ 40 in. Where you're limited to DP 1.4a. This also means that video impacts write performance in case of storage, not read performance.

Yes, in the real world, it can make a difference. But mainly compared to laptops that had a cut down implementation. For example, TB4 requires four PCIe links. Previously, four were optional and only two were required. They also changed how much bandwidth is reserved for video (even if there is no display connected), significantly impacting data-only applications. Which definitely matters in the lower-end segment where you're more likely to encounter the cut down versions. But maximum against maximum configuration, the change isn't that big. It's a good change, don't get me wrong. But it's really more of the same. I wouldn't call it TB4. To me, it's more like 3.1. TB3 with some nice tweaks.

Ah that is very useful, interesting, important and rare info that clears my confusion. Thank you for explaining the differences between DisplayPort in TB and in USB-C Alternate Mode.

Wikipedia does mention this too but in the USB-C article: "All Thunderbolt 3 controllers both support Thunderbolt Alternate Mode and DisplayPort Alternate Mode. Because Thunderbolt can encapsulate DisplayPort data, every Thunderbolt controller can either output DisplayPort signals directly over DisplayPort Alternative Mode or encapsulated within Thunderbolt in Thunderbolt Alternate Mode. Low cost peripherals mostly connect via DisplayPort Alternate Mode while some docking stations tunnel DisplayPort over Thunderbolt."

So a Thunderbolt 3 SSD like Samsung X5 which is connected to an x4 PCIe link TB3 port in my high-end gaming laptop will probably not see any further improved performance for a TB4 port?

Quote from: xpclient on January 25, 2021, 11:18:54

Quote from: _MT_ on January 25, 2021, 08:23:51
TB4 isn't really faster than TB3. In terms of total bandwidth. The main difference lies in minimum requirements. Which can matter, especially in a data-only application (rather than video + data). Other than that, the biggest difference between TB4 and TB3 is USB4 support. And TB3 was available in cheaper laptops.

Actually it is faster in practice even though technically both are "40 Gbps" since as you said, part of it is shared with data for video bandwidth (e.g. DisplayPort alternate mode). But if you connect an eGPU, you get higher fps for Thunderbolt 4 vs 3. If you connect a high speed storage device, you'll get higher throughout. Even though Thunderbolt 4 ports are limited to the same 40 Gbps bandwidth as Thunderbolt 3, the new controllers have to be connected to hosts internally using a PCIe interface featuring a throughput of 32 Gbps, up from 16 Gbps in case of the Thunderbolt 3 controllers (upped minimum requirements). So yes it is really faster. And no, Thunderbolt 3 wasn't present in enough laptops for it to be really considered to have gone mainstream. But with Tiger Lake, it should be present in *most* laptops except the crappy ones like Surface Pro 7+ or Dell Inspiron 15 5502 that go out of their way to remove it.

When you send video + data, you're not using DP Alt mode. That's a USB thing, for one. And it's used when you're sending exclusively video. That's why DP 2.0 can achieve 80 Gb/s in Alt mode using the same technology - video is unidirectional, they can use all links for transmitting. In mixed traffic, you're using tunneling and you have 40 out/ 40 in. Where you're limited to DP 1.4a. This also means that video impacts write performance in case of storage, not read performance.

Yes, in the real world, it can make a difference. But mainly compared to laptops that had a cut down implementation. For example, TB4 requires four PCIe links. Previously, four were optional and only two were required. They also changed how much bandwidth is reserved for video (even if there is no display connected), significantly impacting data-only applications. Which definitely matters in the lower-end segment where you're more likely to encounter the cut down versions. But maximum against maximum configuration, the change isn't that big. It's a good change, don't get me wrong. But it's really more of the same. I wouldn't call it TB4. To me, it's more like 3.1. TB3 with some nice tweaks.

Quote from: _MT_ on January 25, 2021, 08:23:51
TB4 isn't really faster than TB3. In terms of total bandwidth. The main difference lies in minimum requirements. Which can matter, especially in a data-only application (rather than video + data). Other than that, the biggest difference between TB4 and TB3 is USB4 support. And TB3 was available in cheaper laptops.

Actually isn't it faster in practice even though technically both are "40 Gbps" since as you said, part of the data bandwidth is shared with video bandwidth (e.g. DisplayPort alternate mode). But if you connect an eGPU, you get higher fps for Thunderbolt 4 vs 3. If you connect a high speed storage device, you'll get higher throughput. The new controllers have to be connected to hosts internally using a PCIe interface featuring a throughput of 32 Gbps, up from 16 Gbps in case of the Thunderbolt 3 controllers (upped minimum requirements). So yes it is really faster. And no, Thunderbolt 3 wasn't present in enough laptops for it to be really considered to have gone mainstream. But with Tiger Lake, it should be present in *most* laptops except the crappy ones like Surface Pro 7+ or Dell Inspiron 15 5502 that go out of their way to remove it.

Quote from: xpclient on January 24, 2021, 18:22:17
This year's (Tiger Lake) ThinkPad refreshes are exciting because besides renewed competition between AMD and Intel, for the first time we are getting Thunderbolt 4 in affordable laptops. USB 3.0 Gen 1 is simply too slow now and cannot keep up with the pace of internal NVMe storage so faster external I/O going mainstream was way overdue.

TB4 isn't really faster than TB3. In terms of total bandwidth. The main difference lies in minimum requirements. Which can matter, especially in a data-only application (rather than video + data). Other than that, the biggest difference between TB4 and TB3 is USB4 support. And TB3 was available in cheaper laptops.

I really wish someone would test the MSI stealth 15m, yes it doesnt have the H35 CPU but the i7 1185G7, Short power limit of 58w and long power limit of 48w 

https://www.youtube.com/watch?v=VT60qhUbKkk&t=1s

This year's (Tiger Lake) ThinkPad refreshes are exciting because besides renewed competition between AMD and Intel, for the first time we are getting Thunderbolt 4 in affordable laptops. USB 3.0 Gen 1 is simply too slow now and cannot keep up with the pace of internal NVMe storage so faster external I/O going mainstream was way overdue.

Besides, Thunderbolt also allows very useful and interesting things like 10GbE networking via a cheap TB to TB cable between 2 laptops when you want to transfer a huge amount of data via Windows network and Gigabit Ethernet isn't fast enough. Then there's eGPUs and docking possibilities. It's just great.

I am eager to try ThinkPad L14 Gen 2 (Tiger Lake) to see how it performs against E14 Gen 2. The 15.6 inch refreshes should also be very enticing upgrades because of the full numpad you get and a bigger nicer screen.

You seem to be confused about what is TDP. It's not a power limit. As a concept, it exists for cooler selection. Unfortunately, it's useless. As manufacturers of coolers will tell you. Because modern processors can, essentially, automatically overclock themselves. A better cooler can often give you better performance. As temperature is one of the parameters that control this process. I doubt Lenovo is actually using 30+ W TDP. Because that option just doesn't exist. But that doesn't mean the CPU can't draw more than 30 W.

God I hope this becomes a trend (35W CPUs in mainstream again).
So tired of these U's, from both silicon giants.
Give me ARM, or give me H. I want the FULL Windows experience - for everything else, an ultraportable will suffice.

While Intel increases TDP, Lenovo can safely put the AMD Ryzen 7 5800HS or 9 5900HS into their 14" and 15"  ThinkPads.

The T15 has so much pointless empty space, you could add an RTX 3060 Max-Q to the above AMD processors.

We need a Lenovo ThinkPad X1 Extreme with AMD Ryzen 9 5900HS + RTX 3060 Max-Q.