We have learned a lot with our time spent overclocking and gaming on the ASUS R9 290X DirectCU II OC and the GeForce GTX 780 Ti. Our overclocks may seem lower than other sites, but that is because we will not accept any room for instability or artifacts after prolonged sessions of gaming. We want to achieve an overclock that a gamer would set, and forget. We don't just run benchmarks, or timedemos to stress test, we actually play the game, whole levels, whole chapters, even half the game itself at times, to find out what is stable. Multiple hour long sessions of Battlefield 4 Multiplayer are common practice for testing overclocking.
We have definitely determined that "warming up" every video card has to be done to properly get a handle on a video cards real in-game performance for prolonged gaming sessions. This goes for the AMD R9 290X and the GeForce GTX 780 Ti as well, which does have a dynamic clock.
We found that the GeForce GTX 780 Ti would start off at 1006MHz real-time frequency in games for about ten minutes, then slowly drop to a level that it mostly stayed at the rest of the time. If someone were running a benchmark, or timedemo, which usually exist inside that timeframe, it would be showing inflated performance. It is not until you let the cards heat up and game with these for at least 30 minutes that clock speeds settle down.
We found this an important part of testing and finding the best overclock for our video card. What might be stable for ten minutes of gaming, wasn't for hour long sessions of gaming.
The ASUS R9 290X DirectCU II OC video card never throttled on us while overclocking, unless we turned down the power target or fan speed too much. As long as we kept the fan high enough to achieve lower than 94c temperatures, the GPU would not throttle. Our overclock has the temperature at 90c, which was perfect, no throttling at all.
Overclocking Results
For the ASUS R9 290X DirectCU II OC we managed to overclock the video card to 1115MHz with a 1.35v setting and 5.67GHz memory. Remember, the video card is already overclocked at 1050MHz versus 1000MHz on a reference card.
The reference cooler and reference cards are notorious for throttling performance. We experience no throttling what-so-ever on the ASUS R9 290X DC2 OC video card while overclocking. This means we saw a consistent 1115MHz clock speed in every game.
It is important though that the temperature remain below 94c in order to achieve said non-throttling. That means a fairly high fan speed of 75%, which is not a leaf blower, but certainly on the level of, if not slightly louder than the reference cooler fan in Uber mode. The GeForce GTX 780 Ti fan doesn't reach that level till around 80%, but any higher is definitely not going to be liked by most anyone.
Basically, 100% fan on both cards is unusable in a real-world situation. No one would game like that. Unfortunately for the R9 290X, it really needs better cooling to raise the voltage even higher.
Overclocking on Air Has Its Limits with R9 290X
We had our ASUS R9 290X DC2 OC running at 1.35v, and it took 75% fan just to keep it from going over 90c. That's a lot of fan just to keep it from the throttle point. The R9 290X GPU is not built for extreme overclocking unless you are on water, or have some super duper custom air cooled card that isn't out yet. On water we could see 1.4v being a reality, and perhaps that will allow you to edge a few more MHz out of it. On air, 1.35v should be your limit, I'd be worried about damaging the GPU at anything above that on air.
Low MHz Mega Hurts
While our overclock is low compared to previous generations, we think it has more to do with the GPU's limits than the video cards. The video card seemed right capable of pushing the GPU harder. However, the GPU just wouldn't take it.
In our Performance Variance article we noticed how even among the exact same cards hardware differences can create different performance profiles. If the AMD R9 290X is that sensitive to performance differences imagine how much variance there must be in each different R9 290X GPU itself. You may get one that just won't' budge much on overclocking, and from the same manufacturer you might get another one that overclocks by leaps and bounds.
This is what we think is going on, variance among GPUs. If you thought overclocking varied per GPU in the past, we think the condition is even more prevalent on the AMD R9 290X. Hawaii just wasn't meant for 28nm, the architecture inside is ahead of the packaging process available. If only 22nm were ready we think the R9 290X would be showing itself in a whole different light.
The Bottom Line
The bottom line is this, on our first attempt at overclocking a custom AMD R9 290X based video card, we are left wanting. We get the impression that the AMD R9 290X GPU is just not good at being overclocked. We base this on the fact that it consumes an abhorrent amount of power as you increase voltage, which in the process creates a crap ton of heat that needs to be displaced. All of this has to be done just to achieve a decent overclock out of it.
The fact that the AMD R9 290X video card needed a custom card configuration and custom cooling solution just to run at its stock "up to" default 1GHz without throttling is not a good sign. That then limits the potential for overclocking the GPU since the custom card and cooler are already working overtime just to run the card at its normal clock speed.
It will take some massively grotesque custom cooling on air to get the most potential out of the GPU from overclocking and also not sounding like a jet taking off. There are many manufacturers who do partake in the ultimate enthusiast based graphics card, ASUS being one of these with its MATRIX line. We don't' know if that is planned, but it is going to take that level of video card and cooling to get the most out of the AMD R9 290X on air. What an absolute beast of a GPU, and we don't mean that in a good way.
None of this is ASUS' fault, ASUS has designed a stellar video card with the ASUS R9 290X DirectCU II OC. We love this video card from an engineering standpoint in every which way. We are literally drooling at the lip over the amount of design and high-end components that went into this video card to give the AMD R9 290X the best chance it can have in a two slot design.
The only issue with the ASUS R9 290X DC2 OC is the MSRP $569.99 price tag, and the unavailability of it still. (Editor’s Note: As we are going to publish, we have finally seen a price of $699 from Newegg.) It is due out this month, but currently prices are jacked up beyond reason due to high demand of R9 290/X for mining. Hopefully these prices will stabilize and fall back down to where they need to be, but in the mean time, it does mean a more expensive purchase than it was intended to be.
If pure performance is your thing, it looks like an overclocked GeForce GTX 780 Ti may be in your future, which is showing to sell for $719.99 with Free Prime Shipping. We have a retail card undergoing a full evaluation, and that should show us the potential of what a custom card can provide. If overclocking is not your thing, the ASUS R9 290X DirectCU II OC still competes quite well with the GTX 780 Ti, beating it most of the time. Just don't overclock the 780 Ti and embarrass the AMD R9 290X GPU, that way your R9 290X GPU will stay all warm and fuzzy inside.