Conclusion
There
is acutally one crucial reason why we chose the R9 290X for this test. This chip
is known to become quite hot and to then start throttling. Equipped with the
reference cooler the situation is even worse than with this version of the
DirectCU II cooler, which is actually a powerful aircooler for graphics cards.
Nevertheless, when we started to overclock the card we reached the limit of the
aircooler - apparently. At this point we're going to walk through the results
gathered on previous pages and then we add a few of our thoughts.
Running the card at stock clocks shows, that when we equipped it with the EK-FC
R9-290X-DCII watercooler scores were on average 1.6 percent higher than with the
aircooler. This is actually already a solid hint, that the card started to
throttle with the powerful DirectCU II aircooler, even at stock clocks. There
was actually only one game where we couldn't measure a performance difference,
which is Battlefield 3. In this case fps were exactly the same. On the other
hand there is Bioshock: Infinite where we see that the watercooled card is no
less than 6.5 percent quicker. When it comes to stock clocks we also had a look
at two theoretical benchmarks, which are 3DMark and Unigine Heaven 4.0. In
3DMark the differences between watercooled and aircooled are tiny, but in
Unigine Heaven 4.0 there is a 5.4 percent gap.
Once we started overclocking the cards, we noticed that 1150 MHz on the GPU and
1500 MHz on the memory were maximum stable clocks to run the card aircooled with
the DirectCU II aircooler. In order to show there is quite some potential still
slumbering in the R9 290X cooler, when appropriately cooled, we overclocked the
card a little bit hihger. In this case we ran itz at 1200 MHz GPU clocks and
1500 MHz memory clocks. In fact, watercooled max stable GPU clock was 1310 MHz,
but we did not want to drive the chip at its limit since we believe that 1310
MHz is a rather high value and if we want to compare these results to another R9
290X watercooled that card then might not reach these clocks stable.
Let's discuss the results now. In 3DMark Fire Strike Extreme we see the scores
increase by 6.4 percent in case of aircooling OC and 12.6 percent when it comes
to watercoolin OC. This means there is a 6.2 percent gap inbetween aircooling
and watercooling, although the difference in overclocking is only 4.34 percent.
This - again - indicates that the R9 290X DirectCU II with aircooler was
throttling, not much, but it was. When we run Unigine Heaven 4.0 we even notice
that the result, in case of the aircooled OC tests, dropped under the non-OC
value. This apparently shows there was some rather heavy throttling going on and
the chip is constantly hitting the temperature target. The same card, equipped
with the EK-FC R9-290X-DCII did throttle at all and the performance goes up by
11.3 percent. Overall the aircooled version is able to gain 8.7 percent
performance with the overclocking and the watercooled variant got 12.9 percent
faster. One value that was especially interesting at this point was Battlefield
4. In this game the watercooled and overclocked cards gains no less than 25
percent, whereas the aircooled and overclocked card only gains 10.7 percent.
On another note we had a closer look at temperatures. There is actually nothing
much to say then the obvious. Even under full load and overclocked the
watercooled card didn't get hotter than 53°C, whereas the aircooled version ran
at 81°C.
Last but not least we want to add a few thoughts. Putting the results into
persepective shows, that the R9 290X with an aircooler is running really hot.
It's basically hitting the temperature limit as soon as there is heavy load and
even the powerful DirectCU II cooler from ASUS is not powerful enough to
eliminate throttling completely. On the other hand, if you put a watercooler on
top of this card, then you can basically unleash the full potential of this
card. This becomes especially clear as soon as you start overclocking the card.
In our case it was possible to run the card stable even at 1310 MHz GPU clock,
whereas the maximum with the aircooler was at 1150 MHz. Overall we can say if
you go get yourself a high-end R9 290X and you want to get the maximum out of
this card, then we'd recommend you to go for a custom watercooling loop and the
EK-FC R9-290X-DCII is certainly doing a great job. Obviously if you do not own
any watercooling gear at all, this is going to cost you quite some money, but at
least you'd have to buy a new radiator and pump only once. If you buy an new
card in a few years you just need to buy a news waterblock. The EK-FC
R9-290X-DCII we've used for testing in this article is going to set you back
102.96 Euro (price 04.03.2014). To add some more numbers you can for example
calculate that when you overclock the card to 1200 MHz on the GPU and 1500 MHz
on the memory performance goes up by 12.9 percent. The ASUS R9 290X DirectCU II
costs 532.99 Euro (price 04.03.2104 Geizhals). This means for an additional 12.9
percent performance you have to pay an additional 19 percent. If you keep in
mind, that our card was capable of running even above 1300 MHz on the GPU you
can imagine, that the performance gain is going to be somewhere in the ballpark
of 20+ percent.