Inconsistent - Mac Pro monitor not waking up

Okay... here's another question that ought to be easier to answer.

How many of the Mac preferences is it okay to delete in order to fix whatever mysterious thing is wrong with my monitor failing to wake up consistently?

In the old days deleting the preferences would fix all manner of ailments.

So I see there's quite a list of preferences in the HD > Library > Preferences > System Config and also in other locations. HOW MANY of them is it advised to delete to try to fix whatever is ailing my Mac Pro?

Today I had to reboot 2 times... yesterday another 3 times... it's getting to be a pain.

I've run the Disk Utilty, reset the PRAM, unplugged the power cord... I've changed the energy saving choices, I've changed the sleep button to the power button. I've unplugged the monitor's USB port connection... I've tried it all and it keeps on happening. I'm out of new ideas.

Thanks in advance..

OK... here's what seemed to finally work for me. First I spent 2 weeks scouring the internet looking at every manner of fix. None of them worked for me. In fact the problem got worse and worse.

I tried nearly all of these except for reloading Snow Leopard http://reviews.cnet.com/8301-13727_7-10334378-263.html?tag=mfiredir

NONE of those worked. But when I got to my 2nd Apple help person he suggested this.

1) Power down the computer

2) Unplug the monitor

3 Power the computer back on... wait till it has rebooted completely

4 Plug the monitor back in.

Now it seems to be working... (fingers crossed)

I won't mark this as fixed just yet. Maybe in a week or so if the fix lasts.

Nope... once again it failed overnight. But it DID act better after I had unplugged and replugged the monitor cable.

There was a distinctly quicker and more definite action of the monitor starting up quickly on command.

I notice that usually in the mornings the computer is running when I come in.

I have the settings for energy saver at 'wake for network activity' unchecked.

Anyone have any ideas what might be going on to cause it to keep waking up even with the energy saver locked?

And how does it keep coming unlocked every time after I have to reboot it?

Also... is it harmful to one's computer to just shut it down every night?

I figure that it might be because of the motherboard being constantly heated up all day and then cooled and shrunk down at night.

Any opinons? Is anyone out there? Anyone reading this thread?

Thanks!

The FINAL solution? It was the MEMORY!!!

Yep... after spending 2 weeks working with an Apple tech engineer, they said it might be the memory.

I had just installed a 2 gig DIMM into my last available slot. The memory was from Crucial and it was exactly matched for my early 2009 machine. So there is no logical explanation as to why it caused the sleep monitor issue.

However... ever since I removed the new DIMM the monitor sleep issue has been cured. So I'm saying it WAS the memory. I read somewhere about how the newer memory dimms have weird issues... but I can't remember the article. So... case closed... I'll have to live without that extra 2 gigs of memory I guess.

It's better than having to reboot the machine 6 times a day!