Fastest email client

Hello,

I'm currently using outlook express on XP. It starts up and checks email in less than a second. It uses hardly any system resources. I like this.

I'm getting a new laptop with W7---can't use OE any longer (not compatible).

So which client should I use? I don't care about extra functionality, fancy graphics or other bloat. Just speed in starting up and checking email (I heard windows live/thunderbird mail are slow and a significant drain on resources)

I really don't like the idea that I'm upgrading to a MUCH faster PC only to end up with a slower email experience.

thanks in advance