[NSFW] White screen error when using plugin WP super cache

Hi guys,
I’m a webmaster of WordPress website. It’s all about pictures (especially [NSFW] hot girl‘s pics). Now, the data of my website is so large. And the speed loading web is also very bad. I want to speed up the loading speed of my website, so I used plugin super cache. However, I can’t understand why it’s error. Website can’t be loaded, it appears the white screen only. Anyone can help we out of this problem? Thanks in advanced!