Do you work for Club-3d by any chance?

yes i do.
Generally speaking it is not often interesting to repair an out of warranty Graphics Cards like R9 270. Unfortunately we cannot do that here, so the card would need to be send to the Factory in China where they can determine if it can be repaired. Shipping cost alone I estimate to be about 60 USD back and forth without any garanty that your card can actually be repaired.
I mean if the card is completely dead it is most probably either the Power Circuit of the GPU itself, both very difficult to repair if at all possible … 
If it could be repaired we are looking at cost of between 75 USD and 125 USD so plus shipping that would make somewhere between 135 and 185 USD of cost.
This is just an estimate base on the info i have now to give you an idea on “how and what”.

Thank you for the information – I think it’s probably cheaper to buy a new card at this point

Club3D Warranty is normally 2 years, unless you buy it under different terms from a shop or etailer. The chance that the Card is out of warranty fo us is quite large, but by all means do check that on the invoice form the place you purchased it from. Not sure what the extended warranty through your credit card will cover, you would have to check that with them.

very welcome