Overloading rails could definitely cause issues. Which exact psu do you have? I though evga psu’s were single rail units, so you don’t have to worry about such issues.

Sajin
No problem. Your call at this point on what you want to do. I’d opt for a new single rail psu.

 
They are all really single rail, it's just the OCP is broken up between the different connections on the PSU. 
 
Added safety feature so one connection doesn't get overloaded and melt the connections as an example.
 
The OCP will trip at 20 AMPS instead of taking the whole 80 AMPS before it would trip otherwise. 
 
 

mkosto
Actually funny thing I run Furmark to test, and the nobreak was the one that got tripped xD

 
Well, what can you do....
 
Time for a new PSU.
 
20A is actually a pretty low limit for a multi-rail unit. I was hoping for the best for you.
 
Mine has 7 rails @ 40A per rail, each connection is on it's own rail.
 
The new one I have coming has 17 rails @ 40A per rail, again each connection is on it's own rail.
 
 
 
 
 
 

cneuhauser
Why not go with a single rail PSU?
 
The only reason a PSU has rails is to supposedly be "more safe"... which in my opinion is a load of garbage in this day and age.

 
Actually it's NOT.
 
Especially with the higher powered units. For a 1600W PSU that's 133A on the 12V+...
 
The issue that can happen with a single rail PSU say a 1000W unit as an example.
 
Say a part goes bad and the PSU will keep feeding power to it, up to the max amps the PSU can provide. 
 
That's a melted connector right there. And the PSU will keep feeding power to it until the OCP or OTP kicks in... After the connector has already melted. That's 83A on a 1000W PSU.....
 
Or a wire gets pinched, same story, the PSU will keep feeding more power until it hits the max it can provide. The pinched wire causes resistance so the PSU needs to feed more power through that one connection to correct it. And will continue to feed more power until it hits max power and or until the PSU overheats. That's 83A through one connection....
 
Things do happen, not all the time, but they do.
 
With the newer Multi-rail PSUs some are Multi-Rail, Single Rail switchable.
 
Some also have adjustable OCP on each rail.
 
For 750W and under I wouldn't bother with a Multi-Rail unit, 850W and over yes.
 
They are all Single Rail PSUs......
 
The difference is the OCP is broken up over the different connections on a Multi-Rail unit. So if one connection gets overloaded as the example I pointed out above the PSU will shut down once it hits 40A on that connection instead of 83A on that 1000W PSU.