Website downgrade

I’ve had reasonably high traffic levels recently, with the svchost and Derren Brown posts getting lots of attention. As a result my website keeps falling over for unknown reasons. ‘Reasonably high’ is only ~500 visits per day, which isn’t much by the standards of many blogs, and I definitely shouldn’t be having these kind of problems. I turned on a caching program which this afternoon broke, serving blank pages. Argh. I’ve downgraded to a theme that’s very easy on the server and shall monitor it for a few days. Early indications are it’s not making much difference, which is just weird.