Nvidia GTX295 Quad SLI

Test Setup

To ensure that all reviews on Overclock3D are fair, consistent and unbiased, a standard set of hardware and software is used whenever possible during the comparative testing of two or more products. The configurations used in this review can be seen below:

i7 Rig

CPU: Intel Nehalem i7 920 Skt1366 2.66GHz (@3.835 GHz)
Motherboard: Gigabyte X58 UD5
Memory: 3x1GB Kingston HyperX DDR3 2000MHz @ 9-9-9-24
HD : Hitachi Deskstar 7k160 7200rpm 80GB
GPU: Zotac GTX295 / XFX GTX295
Graphics Drivers: GeForce 182.06
PSU: Gigabyte ODIN 1200w

 
Setting up SLI was a painless experience. I simply plugged the first card in, installed the latest drivers from Nvidia (182.06), shut down the system and installed the second card. The second card was identified and after a few automatic screen refreshes later the installation was complete. I then went into the Nvidia control panel to enable SLI and to set the PhysX acceleration and went to the device manager to check all GPU’s were present (see below) and that was it, job done.
 
4x295 SLI Setup
Power requirements

You will most certainly need a powerful PSU to run two of these cards in SLI along with a high end base system. Luckily for us our test rig’s PSU, a Gigabyte Odin 1200w was up to the job but Nvidia recommend a 1000W PSU for these cards with good cause as we show below.

Below right I took a shot of the SLI’d cards to highlight the Blue LED which is redundant in single card configuration. While not exactly ground breaking it is a useful add-on that reduces the trial and error when plugging in your primary monitor.
 

Power SLI
 

During the testing of the setup above, special care was taken to ensure that the BIOS settings used matched whenever possible. A fresh install of Windows Vista was also used before the benchmarking began, with a full defrag of the hard drive once all the drivers and software were installed, preventing any possible performance issues due to leftover drivers from the previous motherboard installations.

To guarantee a broad range of results, the following benchmark utilities were used:

 
3D / Rendering Benchmarks
• 3DMark 05
• 3DMark 06
• 3DMark Vantage

3D Games
• Crysis
• Far Cry 2
• Oblivion


• Bioshock
• Call of Duty IV
• Unreal Tournament III

Power Consumption

Power consumption was measured at the socket using a plug-in mains power and energy monitor. Because of this, the readings below are of the total system, not just the GPU. Idle readings were taken after 5 minutes in Windows. Load readings were taken during a run of Crysis.

 

 
As you can see the full system draw of our test rig with two GTX295’s is massive. A ‘normal’ high end test rig is likely to be even higher than this as our rig had no extra fans, hard drives, watercooling etc to power so ensure you have a meaty PSU to power your setup.
 
Temperatures

Temperatures were taken at the factory clocked speed during idle in Windows and after 10 minutes of running Furmark with settings maxed out (2560×1600 8xMSAA). Ambient temperatures were taken with a household thermometer. As we use an open test bench setup consideration should be given to the fact that the temperatures would likely increase further in a closed case environment.
 

 
Surprisingly, adding a second GTX295 did little to affect the temperatures of the cards. I should state however that the noise output of the cards, even at idle, was clearly audible. On full load the cards were noisy enough to become distracting but this is outside of a case environment so it is likely the cards noise would be subdued somewhat in an enclosed space. I would still recommend a good set of headphones or speakers to drown out the whooshing noise nonetheless.
 
Let’s move on to our suite of benchmarks where we pitch it up against the ATI 4870×2 and XFX GTX295 in our full suite of GPU benchmarks…