Quote Originally Posted by vinister View Post
I am very careful tightening the screws and closely watch the card so its not bending. My question is this: Just how tight should the screws be? Theoretically, if there are many mounting screws and everything is machined straight, then shouldn't the block actually straighten the card as you tighten it down?

please elaborate on how to 'be careful' while taking this risk.
Careful means screwing the screws with feeling. When you feel there is a contact of the block with card, you should turn the screw for about 180°. Sometimes less sometimes more, it's in the feeling.

About straightening the card. This would be possible only if the mounting holes would be positioned on right spots to straighten the card. But most common position is that the card will have to bend a little as the screws are not perfectly placed.