When was this?
Like Dyver said, after the last time the graphics were updated the black screens have become worse, for me too. That update was in June.
https://www.eveonline.com/news/view/patch-notes-version-20-06
If you had no problems after June, yet your problems started more recently there might be another or an additional cause.
I saw a post mentioning that the Photon UI took more memory than the old UI, if you are one of the people who are playing with the new UI now, give it a try with Photon turned off to see if you get any improvements?