Once again, our basic test system is identical to the one we used for both the initial review and the Three-Way SLI review. The only thing that has changed was the GPUs used and we removed the SATA 3.0 drive. The rest including the installation of Windows 7 was left the same.
Of course, now we have a slight issue; the AX1200 Gold only has enough ports for Three-Way SLI. There are six 12-Volt (8 and 6 pin) connectors for PCIe. This could mean that the AX1200 Gold will not support all four GTX 480s. We will have to use adapters to add the fourth GPU in. This time the culprits are GIGABYTE's GV-N480D5-15I-B.
As you can see, using adapters makes things a little messy on the test bench, but it would seem that we can physically arrange things. Now we have the issue of worrying about if the 100 Amps on the AX1200 Gold's 12V rail is going to be enough. Of course, if the X58A-UD9 is not efficient enough, we will have some trouble here.
GIGABYTE claims they have tweaked the voltage regulation to ensure efficient power to the board. This is a good thing, as if some of the things we have read are to be believed a single GTX 480 can use almost 40 Amps. This would mean 60 Amps are needed for SLI (1.5 single GPU load is the rule of thumb), 80-90 Amps are needed for Tri SLI and over 130 Amps would theoretically be needed for four-way SLI.
Of course, we have a hard time believing that the GTX 480 would need almost double what the GTX 470 needs. We are thinking that we may still be able to sneak in under the power curve of the AX1200 Gold, but it will be close.
Cooling was another concern and we had to break out our fans again. This time we needed one to blow air in and also across the SLI Bridge. We were surprised to see how hot that little piece of hardware got during use. But with these two fans in place, we were all set for testing.
In the end the first test was also one of the hardest on the system. Believe it or not, 3DMark Vantage does use up quite a bit of power and can push a GPU pretty hard. However, the X58A-UD9 and Corsair AX1200 Gold was more than up to the task!
Of course, it was a close thing; the X58A-UD9 is more than up to the task, but the PSU is probably right on the line. We decided not to push our luck and try to overclock the CPU or GPUs at this time. As you can see, just under the load of the four GTX 480s and our test setup, we were well over 1000 Watts of power drawn from the wall. Still, like we said, the X58A-UD9 was able to pull it off nicely.