Automatic backup Vs Manual Backup, pros and cons?

Hi everyone,

I was wondering what your opinion is regarding automatic backups of your forum. I have mine set to automatically backup my forum but I'm beginning to wonder about some things.

1) Does anyone know what time these backups occur at... are all forums backed up at the same time?
2) Is it possible that these backups are the cause of the server problems that have been happening?

I've noticed that nearly every night (my time here in Canada) around 9pm EST, my forum tends to slow down. I've also noticed that it's always been around this time that the major server problems and/or outages have started in the past.

I'm just curious if there is a connection between the automatic backups and the slow downs and server crashes and outages. I wonder if I set my backups to be manual, if this might be better and avoid problems. I also have noticed that not all forumotion members are affected all the time by these server problems. Could it be these people do their backups manually?

Your thoughts, ideas, insight?