Are cables from Supernova 850 GT and GA compatible?
 
Also: Can I plug in a VGA power cable with any end into the GPU?
I noticed you unfortunately made the connector too big to fit into the PSU on one end, so I shaved it down so it can fit both ways, just want to make sure that the pins are compatible, even tho I had to shave down the hook that holds them in...
 

 Why did I shave off the connector?
Because it's a split connector and looks ugly on the GPU end, also some of these cables have 2 connectors on the GPU side, and that looks even worse if there's an unused split cable hanging off the GPU, naturally... so I wanna plug them in reverse...

Based off this post I would say they are compatible. I would not plug them in reverse. You had to shave it to fit, so that tells me no they should not be plugged in reverse.

thank you.
looks like the cables are compatible EXCEPT the big MB cable:
"Thank you for reaching out.  Our recommendation is always to use the cables that came with your power supply when upgrading, in this case the GT.
 However to help you a bit, the GA and GT cables are mostly compatible between these two part numbers.  The GT does have a slightly different MB (24pin cable).  If you swap the supplies, make sure to use the correct MB (24pin cable).
 Regards,
 -Jayson- EVGA USA RMA Dept."