Cintiq companion 2 as 2nd monitor issue

[wacomanim]

Here is what I have been trying to resolve for several months without success.
When I record my screen with recording software, I lag heavily and it is impossible to draw correctly. Everything becomes too slow and unusable.
So I thought of the following theoretical approach: using a 2nd screen to duplicate my display and record the screen of the second screen.
I have two identical companion 2 cintiqs on windows 10. So I would like to use one of them as a second screen.

Nevertheless my two attempts ...

1- with a mini display port to hdmi adapter cable

2- a usb 3.0 to hdmi adapter cable

... did not work. In the first case, no display and no detection. In the second case, a second monitor seems to appear in the w10 parameters but impossible to switch to the 2nd screen. The screen goes black for a few seconds and remains on the 1 st screen.All others mode as duplicate extend etc. did'nt work neither.

After some research I read that some cheap cables don't work well with cintiqs.
And that we had to privilege the startech and kanex brands. So I returned the other 2 cables and I'm about to buy a startech cable. But I don't know which of the two to choose.

1-https://www.amazon.fr/StarTech-com-Adaptateur-vid%C3%A9o-Mini-DisplayPort/dp/B00LV9SUVU/ref=sr_1_4?__mk_fr_FR=%C3%85M%C3%85%C5%BD%C3%95%C3%91&dchild=1&keywords=startech%2Bmini%2Bdisplayport&qid=1607985390&sr=8-4&th=1

2-https://www.amazon.fr/StarTech-com-Adaptateur-vid%C3%A9o-Mini-DisplayPort/dp/B01M24BCN3/ref=sr_1_4?__mk_fr_FR=%C3%85M%C3%85%C5%BD%C3%95%C3%91&dchild=1&keywords=startech%2Bmini%2Bdisplayport&qid=1607985390&sr=8-4&th=1

Some information is difficult to find such as:

- What is the version of the CC2 mini display port? 1 ? 1.2 ? 1.4 ?

- Until what technology can it works efficiently ? 2K, 4k ? 30htz ? 60 htz ?

- On which will it draw the best performance ?

- Is it compatible with a 4k cable at 60 hertz ?

Please guide me to make the right choice because I am lost. I dont know what affect the display rate or any parameters de résolution.
I am also listening to alternative solutions to record a screen without lag from the CC2.
Actually, I didn't think using a 2nd monitor would be such a hard task. I have tried several screen recorders without success.

Thank you in advance for your help !

[wacom5]

Adding a second display will not reduce the lag. Screen recording can be very taxing for your system and adding an extra display will only consume more resources. For starters, make sure your system has the latest drivers installed.

My recommendation: look for a screen recording software that has low requirements. I can't recommend a specific one but there are plenty on offer. If you are experiencing lag, lower the captured frames per second and the resolution.

[wacomanim]

Thank you for your prompt response. I will try to lower the resolution and the fps.

Regarding the startech cable

which one should i use to connect my two cintiqs companion 2 (premium i7 256 ssd, 8g ram, intel iris 5100, w10)?

- Startech 4k 60 hertz or 4k 30 hertz?

[wacom5]

The Cintiq Companion 2 is not able to output 4k @ 60Hz (limited by the processor) so you can get the 30Hz option.

[wacomanim]

Thank you for the information.