Thinkpads Forum

Hello,

it is well-known that in Intel platforms the deepest package C state to which transition is possible depends on screen resolution. In Haswell systems (T540p), having a WQHD (2880x1620) display panel effectively limits you to PC3 state and consequently 11W idle power consumption (in Linux). If I reduce my display resolution to 1024x768, power consumption instantly drops to 7-8W, yielding a significant saving. However, if PSR (Panel Self-Refresh) is active, then there are no limits on package C-state and power consumption then depends on actual frequency of changing the on-screen content (which is quite low in my case).

Obviously, panel self-refresh must be supported by both the chipset and the panel. As far as I know, PSR support in T-series panels appeared in T*60. Hence here is the question: is it possible to plug a display panel from T560(p) into a T540p laptop — i. e. are they electrically compatible? Or maybe there are other options of PSR-enabled compatible display panels?

Get the datasheets from a T540 and T560 or similar LCD and compare the LCD-connector pinouts.
If they are the same (and in the same position), you can swap screens.

RealBlackStuff wrote:Get the datasheets from a T540 and T560

Uh-huh. I'm having trouble finding part numbers for T560's panels and I have no clue which panels are "similar"; that's why I'm writing here in the first place.

Actually, if anybody who runs Linux on newer 15" ThinkPads here is reading this, then please tell me the output of along with your thinkpad model and (if possible) your display panel part number.

intelfx wrote:I'm having trouble finding part numbers for T560's panels

Here is the one for the T560 (check page 4), and here the one for the T540/p (check page 8 )

Tasurinchi wrote:Here is the one for the T560 (check page 4), and here the one for the T540/p (check page 8 )

Thanks. That's a pity — same part number for WQHD panel... (i. e. no PSR on T560 in fact)

So, on to the plan B. Does anyone know of a 15" ThinkPad with WQHD display and PSR active?