Improve load time/ first time to byte of slow website

[J.Mulder]

Hello,
I start to get a little desperate because I don't know where to look any more. Hope you can help me.

I have two websites hosted at CloudVPS (http://www.cloudvps.com). On my Windows VPS there are two websites: http://www.ledub.nl and http://www.johnmillershirts.nl. The websites are made in .NET and use Umbraco as CMS. The technique is the same, the DB, the DB structure, configurations, settings, photo's/ pictures are down sized, everything is compressed, Gzip....everything is the same (at lease as fas as my knowledge goes and what I have checked).

The only thing that is different and is really getting an issue is the loading time/ waiting time/ time to first byte. It takes between 7-11 sec for http://www.johnmillershirts.nl to load and usable for visitors. That is way to long compaired to http://www.ledub.nl (takes about 2-3 sec to load).

What could be the problem? And most important how to solve this? Because we are running our add campains this has a big impact on our revenu. I hope that there is somebody who can and will help me :-)

See the attachment for the testing results. Let me know if more info is needed. Thanks.

Grtz.
Jelmer