Rebuilding the iPhoto library when you start the software should make it run a little faster.

We have so many images in our iPhoto database that sometimes our poor Mac struggles. Like us, you may be wondering... 

What can I do to speed up iPhoto? 

Over time the iPhoto database can become corrupted and sluggish. Some users also report problems with iPhoto’s speed after switching from ‘09 to ‘11. Rebuilding the library should help you claw back some of that lost speed.

To do this, hold down the Option and Command keys when you launch iPhoto. Check “Rebuild Database”. Click “Rebuild”. Take a second passs through and this time choose “Rebuild Thumbnails”. When the repairs have been completed, restart iPhoto.

If that doesn’t seem to work, some users who have had problems with slow speeds in iPhoto ‘11 have found that starting from scratch works even better. You delete your old library, then re-add the photos a new one.

When scrolling through thumbnails in iPhoto, the software can slow down as it redraws each individual one. Try hitting the 0 key to get much smaller thumbnails or 3 to go to medium sized ones.

Set thumbnails to a uniform size, either small or medium, to scroll through them more quickly.

In cases where you’re managing lots of photos with iPhoto, the fixes above should improve overall speed. If they don’t, there’s one, final more drastic solution. 

Related: 

Can I add RAM to my Mac?

Can I upgrade the graphics card on a Mac?

Should I get 4GB or 8GB of RAM in my Mac?