I installed a new theme on magento 1.7, and I also had to uninstall GTSpeed, seeing that was breaking the theme. And now I'm getting 1.9 minutes average TTFB time. I don't believe it is because I uninstalled GTSpeed, there is too much difference.
I installed APC and Varnish, but it didn't help. Magento with the old theme (currently live) delivers the first byte in less than 0.6 seconds usually.
Here is the URL to the test slow version: http://18.104.22.168/musicminds.ie/httpdocs/index.php/
What could possibly be causing this?
EDIT: It's possibly something to do with the 2columns-left.phtml, when I changed the home page to 1 column the TTFB time went down to 4 seconds.