NVIDIA GeForce GTX 690 Dual GPU Video Card Review
Is the GeForce GTX 690 the best dual-GPU video card ever built? We'll compare performance to GeForce GTX 680 SLI and Radeon HD 7970 CFX to see where the new beast from NVIDIA stands. We overclock the dual GPUs and push these as far as we can. Surely this is the best performance ever experienced from a single video card.
Overclocking the GeForce GTX 690 is made simple by using EVGA's Precision Software. We've downloaded the latest version 3.0.2 and had no issues with it detecting our GTX 690 and working with it. EVGA Precision has a check mark box on it to synchronize the GPUs between "SLI" video cards. This means with it checked both GPUs will utilize the same TDP and GPU Clock Offset options we select in the software. We had this turned on so both GPUs would overclock together.
These are the default settings with EVGA Precision. For our overclocking we are going to adjust the TDP, or Power Target as well as GPU Clock Offset and Mem Clock Offset.
During regular operation at default settings we found that the GeForce GTX 690 was running at 1058MHz thanks to GPU Boost in all our games. The baseclock is 915MHz, but GPU Boost was taking the frequency of the GPUs to 1058MHz. We also found that GPU 2 was always the one at 1058MHz, and that GPU 1 was always somewhere between 980-1006MHz. What this means is that one GPU was a bit slower than the other, and we verified this as we played games.
We were in fact able to stabilize GPU 1 and make it go up to the same frequency as GPU 2 simply by raising the Power Target slider to 135%. We noticed that when we did this, GPU 1 would always hit 1058MHz along with GPU 2 and it seemed to stabilize the frequency to always stick at that frequency.
We came to the conclusion that if you are gaming, and want to stabilize GPU Boost between both GPUs, raising the Power Target is the way to go. This will keep both GPUs at the same clock speed, and it won't be overclocking the GPUs. The GPUs occasionally spiked up to 1071MHz, after raising the Power Target, so it didn't affect maximum clock speed too much, it just helped "equalize" both GPUs to each other. So there is a easy tip for stabilizing performance with the GTX 690; raise the Power Target.
Above are the settings we found for the maximum stable overclock over a period of several hours. One thing we make sure when we overclock is that the frequencies are stable for prolonged gaming as there is no point in utilizing an overclock that lasts 10 minutes then crashes. The last thing you want is your Multiplayer BF3 game to crash in the middle of owning your enemies.
With our GPU Clock Offset set to +145 we experienced a real-time GPU frequency on both GPUs of 1202MHz while gaming. At 1202MHz it is an overclock of 144MHz from the GPU Boosted speed of 1058MHz we experienced at stock settings. We know that NVIDIA stated 1300MHz may be possible on these GTX 690 cards, but we were far from achieving 1300MHz with stability.
In order to make 1202MHz stable we had to raise the fan speed to 75%. At 75% fan speed the fan wasn't annoyingly loud, but provided noticeably more air flow. We wanted to set a fan speed that we could keep enabled at all times while gaming. At 75% fan speed we feel you could run this 24/7 without any annoyances whatsoever.
We did try overclocking to 1300MHz with the fan maxed out of course, but it crashed quickly.
We found that the "maximum" we could overclock to was 1233MHz, however this was not stable. After 5 minutes in BF3 at 1233MHz the game would crash. With the GPU Boost frequency at 1202MHz the GTX 690 was stable for hours. We felt that this frequency would be one you could enable and leave on all the time for gaming. It is a decent overclock that did yield performance advantages. At 1202MHz you are of course operating faster than 680 SLI stock and getting better performance that the GTX 680 at stock clocks.
On the memory side of things we opted to sacrifice memory clock speed in order to get engine or core clock speed higher. We could push the memory higher, but this sacrificed our GPU Boost clocks to some extent. We took the memory to 6.4GHz over 6GHz and left it there in order to push the core clock as high as we did. We'd rather run with 1202MHz GPU clocks and 6.4GHz memory than higher memory clocks with lower core clock speeds below 1200MHz. Performance is better the more you overclock the GPUs themselves.
Now we will compare apples-to-apples performance with our new overclock.
The overclock clearly helped performance in BF3 we are seeing a 11.5% performance advantage with the overclock. It helps bring performance over Radeon HD 7970 CFX in this game.
Batman also experienced a performance improvement with the overclock. The overclocked GTX 690 was 11.7% faster than it was without the overclock. It simply blows the HD 7970 CFX away in this game.
In Deus Ex there was a whopping 17% performance improvement with the overclock.
In Skyrim we are experiencing an 8% performance improvement with the overclock.
Overclocking the GTX 690 certainly brings performance over GTX 680 SLI and makes up for the small percentage differences. Note that the highest overclock we've achieved so far on a GTX 680 is 1228MHz here. With the GTX 690 at 1202MHz it is very close to what GTX 680 SLI would overclock to, therefore the overclocked performance of GTX 690 is close to the overclocked performance of GTX 680 SLI. The GTX 690 doesn't seem to be hampered at all in the overclocking department, although we were certainly hoping for that magic 1300MHz number.