Can my Mac Pro take 800MHz RAM?

Question

I recently purchased 2006 Mac Pro that had been modified with a 2007 mother board.
It came with 16GB of 667 RAM and I switched it out with 32GB 800 RAM.
However, in my "About This Mac" page it shows me to have 32GB 667 RAM.
Will my system no handle anymore than 667?
My serial number is: G8*****UPZ
Again, the motherboard has been replaced with a 2007 model.
<Edited by Host>

Answer 1

You are locked into the front side bus's 1333MHz. Generally 2,1 and 1,1 are identical except the 2007 and 2,1 firmware support for 53xx quad core, same socket and bus speed, and 667's have tended to be cheaper than 800MHz. Rare that someone would need 32GB and benefit from more unless they are running large images in CS4+ for one example. In which case a newer 2008 or later or iMac makes more sense.
The best improvement and upgrades are from one or more SSDs for system and your graphic scratch and image libraries, 500GB for less than $250, PCIe SSD (for scratch, not booting t he system).
The 2008's can use 667MHz and I thought that was where the differences and tests were done, not between 2007 and 2006 systems which both used 667MHz like mine is.