Damage due to bad displayport cable?

[bread]

So I bought several displayport cables so I could pick and choose which one works best. Unfortunately I got a lemon that was problematic the moment I started it up. It caused the display and input to lag so much. Mouse movement takes like twenty seconds before moving and jumps inches at a time. Clicking on something and opening a window took minutes at a time. It was pretty much a sluggish slideshow. I couldn't shut down normally because I couldn't move the mouse properly and it was so slow so I did a hard shut off and got rid of the cable.

Thing is after using the bad cable I feel like my display performance is slightly off. That smoothness and input lag are a bit worse by around 3% to 4% from what it used to. Can a bad cable really cause something like this? Is there a way to fix it?

[Chief Blur Buster]

Hello!
Apologies for the delay.
(The "No 0 post threads in General" rule I personally try my damndest hardest to keep up with...)

A bad piece of computer hardware (even a cable) can cause internal events such as an infinite interrupts loop or exception handler loops that bog down the system to a sloooooooooooow crawl.

Now, for aftereffects, it's hard to say. Sometimes it's a symptom from trying to fix an earlier problem (e.g. attempted graphics driver reintalls, or other hardware changes at the same time).

Sherlock Holmes Mode = ON

Now, an elementary question in this detective run.... A common situation when somebody gains new DisplayPort cables, is someone added a new monitor. So....did you add a new monitor?

Discordant-Hz multimonitor can create mouse lag artifacts too
Did you do any other hardware changes, such as going multimonitor? Discordant-Hz multimonitor sometimes creates lag artifacts when a low-Hz monitor has screen activity, slowing down the adjacent high-Hz monitor. This manifests itself as sudden framerate changes. You see it all the time when running http://www.testufo.com simultaneously on two different-Hz monitors. My general recommendation is always try to make all the same high-Hz, or try to minimize all windows on the lowest-Hz monitors when you are doing critical high-Hz stuff. (Except for 100% non-graphics stuff like Windows Notepad, Calc. Unfortunately even a static webpage sometimes still causes problem, because web browsers are now GPU accelerated nowadays). Tools such as DisplayFusion can automate disabling/enabling of monitors. Also games running in FSE (Full Screen Exclusive) will bypass the discordant-Hz interference and will merrily run at the correct frame rate. Windowed mode is currently frequently prone to interference between monitors under Windows 10.