EVGA 780 967MHz model with ACX cooler.
http://www.techpowerup.com/reviews/MSI/GTX_780_Ti_Gaming/23.html
Uber-mode for the R9-290X is similar to non-reference cards:
http://www.pcper.com/reviews/Graphics-Cards/ASUS-Radeon-R9-290X-DirectCU-II-Graphics-Card-Review/Crysis-3
The OC'd 780's also perform 10% faster than stock, thus the card I linked almost EXACTLY MATCHES an overclocked R9-290X except it's not as noisy. A few of the R9-290X cards are okay for noise but most are just too loud.
I looked at several benchmarks to confirm this, and this graph is an average of about 18 games.
I know others will disagree, and vehemently, however I'm just trying to piece together FAIR pieces of data. It's possible that I'm incorrect but if so, not by much. I'm willing to concede the R9-290X might average as much as 5% faster but that could all change with any heat issues, and what is the PRICE DIFFERENCE now anyway?
The R9-290X is roughly $15 more expensive than a comparable GTX780, and an R9-290 is equal (in North America).
Summary:
I find no information that the R9-290X is a better card when you compare two of the best cards from each of the R9-290X and 780 camps. If it is, it's a SMALL margin and other factors are more important such as:
- Noise
- Price
- Games?
- AMD-> Mantle
- NVidia-> Shadowplay, G-Sync, GameStream, PhysX