It doesn't seem to happen for me. I agree about Chrome being much more of a power hog, though, than Opera 21. It's one of the reasons I prefer the Opera browser. I use Windows 7, and have 8 ram. I was wondering what kind of Opera system, computer setup you have. What's your Operating system? Do you have a lot of computer resources? Do you have a lot of tabs open, when this happens? Are you relying on wifi, etc.
Also, how are you opening the link in a new tab. From the context menu (by right clicking on it) you could open the link in a new tab (background view). Or you can middle click on the mouse (and open the link in a new tab in a background view), or shift middle click and open it in a foreground view. Does it make any difference which way you go about opening the link in the new tab?