Video card support plate

No, those are really just for shipping heavy cards.

ok. my old card (GTX260) has a support plate connected to it but it is not a long or heavy card so it seems a bit odd to me.

my new card may be a GTX660 which is 269mm long.
both cards take up 2 slots (39mm high).

here is an example photo just to check we are talking about the same thing:

I've ordered the GTX660 which is 269mm long! It will fit my case and I hope that I don't need a metal support plate (as shown in the photo above). If you guys think I do then please let me know. Thanks.
 

Its fine. The 660 isn't exactly a whale so it shouldn't sag too much.

thanks for your confirm.  

Job done! I installed the lengthy GTX660 today - it didn't have a support plate or any way of attaching one that I could see. It did wiggle a bit but it's in and working just fine / so avoiding earth quakes all should be well.