Lenovo ThinkPad T490s using the same motherboard as smaller X390 may explain feature loss
The ThinkPad X series and ThinkPad T series are the two oldest ThinkPad series that are still on sale today. Both date back to the year 2000, when IBM released their original models, the IBM ThinkPad T20 and the ThinkPad X20. Traditionally, their positioning was clear and separated: The X series were the smallest, most compact ThinkPads, while the T series models were bigger, more flexible and powerful in their hardware while still being pretty portable.
This was true at least up until a few years ago. Since the Ultrabook revolution happened, the T and X ThinkPads started to become more like one another – still, a few differences remained and the T series still had more features.
The newest models of the ThinkPad T & X series were released in February at the MWC. One of the model with the most changes was the Lenovo ThinkPad T490s, the slimmest T series ThinkPad laptop. Some of those changes seemed to spark some controversy online, as the T490s does not feature upgradeable RAM, a full-size Ethernet port or a dGPU option, unlike its predecessor – certainly, the T490s is not a straightforward upgrade of the Lenovo ThinkPad T480s, which offered all those features. Instead, Lenovo opted for a thinner and lighter design.
Slimming the device down might have not been the only reason why Lenovo made these changes though: Lenovo has released the manuals and parts-lists for the new models and they reveal that the T490s and the smaller ThinkPad X390 share a lot of their design cues. Significantly, Lenovo uses the same mainboard design for both the X390 and the T490s, which is unprecedented.
In essence, this means the X390 and the T490s are pretty much the same device, just with a different chassis design and screen size. For Lenovo, the benefits seem clear: Using the same motherboard design is bound to save a lot of money in terms of development and manufacturing. However, this also means that those devices can not be differentiated as much as older models, leaving the T490s without some of the options its predecessor offered.