03-27-2017 07:37 PM
I have a M900 Tiny with three display ports. This unit will only display to my acer display on the top port. The other two it wont.
I took it to work and hooked it up to a 4k monitor and each port worked fine.
I tried another long DP cable at home and it didnt work.
Is it the cable length of the Display port cable?
If so is there a "for sure" workable 15 to 20 foot display port cable out there I can buy.
Confused and tired.
03-28-2017 05:48 AM - edited 03-28-2017 05:53 AM
The DP spec is 3m max for passive cables (longer distances possible depending on resolution and bit depth, and quality of cable.) Active cables are technically required for further.
I've found the products certified by DisplayPort.org to perform as advertised: displayport.org-products-database (check the cables box and click search.)
03-28-2017 03:01 PM
Trying to find a "real" active display port cable is not a lot of fun. I did order one and it will be here tomorrow. I will test it out and see if it really is "active". More on that tomorrow.Great use of quotation marks here. I did also find some display port in-line repeaters but they range from 80 to 100 dollars.
Thanks for the reply!
03-30-2017 07:54 PM
Well an update. I bought an "active" cable and it was intermittant at best. I asked tech support if my M900 with integrated 530 video could push 4k and he said no. Now I look on line and it says Intel 530 can push 4k. More tests to follow.
03-31-2017 07:27 PM
Latest tests... Connected up to a Dell 28 inch 4k monitor with a long dp cable. Works fine. no drops no anything. Running at 29hz only though.
I will be calling Lenovo support on Monday to see if the bios is holding it back from 60hz.
04-01-2017 05:08 AM - edited 04-01-2017 05:14 AM
What brand, model and length is the active cable?
(for our information, can you gave us the same for the passive cable you tried originally, Ty. Do any of them have the DP logo molded into the connector? )