Today we are testing the card in a Intel Core i7 990x system, which is CPU watercooled and running at 4.8ghz.
Processor: Intel Core i7 990x @ 4.8ghz.
Cooler: Danger Den Watercooling.
Motherboard: Asus Rampage III Black Edition.
Memory: 12GB GSKILL 2133mhz Memory.
Power Supply: Corsair AX1200W.
Hard Drives: Patriot Pyro 120GB & 2TB Samsung hard drive.
Optical Drive: Asus BluRay drive.
Graphics: Sapphire HD6990 with reference cooler and Arctic Cooling Accelero Twin Turbo 6990.
We are testing today at the higher bios setting of 880mhz. Remember that the cards won’t be covered under warranty at this setting. We wanted to stress both cores as much as possible.
Room ambient was maintained at 24c throughout testing to ensure accurate results.
At idle, the reference cooler holds a temperature of around 40c. The Accelero Twin Turbo 6990 cooler drops this by 6c to 34c.
Under load, the temperatures are reduced dramatically, by 20c-23c , which is a huge difference and will help ensure maximum PCB longevity. We decided to measure ‘return to idle’ temperatures, highlighting cooler performance.
The video above was taken from our launch review of the HD6990 in March, it shows how ineffective the AMD reference cooler is at dissipating heat.
A return to idle figure of 26 seconds is a class leading result for the Accelero Twin Turbo 6990. The reference cooler takes around 2 minutes to achieve the same results, running close to 20c hotter throughout the curve.
We have built a system inside a Lian Li chassis with no case fans and have used a fanless cooler on our CPU. We are using a heatpipe based passive power supply and an Intel SSD to keep noise levels to a minimum. The motherboard is also passively cooled. This gives us a build with completely passive cooling and it means we can measure noise of just the graphics card inside the system when we run looped 3dMark tests. Ambient noise in the room is around 20-25dBa. We measure from a distance of around 1 meter from the chassis and 4 foot from the ground to mirror a real world situation.
Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on only the video card. It also brings us slightly closer to industry standards, such as DIN 45635.
We load the card with FurMark.
KitGuru noise guide
10dBA - Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA - High Quality Computer fan
40dBA - A Bubbling Brook, or a Refridgerator
50dBA - Normal Conversation
60dBA - Laughter
70dBA - Vacuum Cleaner or Hairdryer
80dBA - City Traffic or a Garbage Disposal
90dBA - Motorcycle or Lawnmower
100dBA - MP3 player at maximum output
110dBA - Orchestra
120dBA - Front row rock concert/Jet Engine
130dBA - Threshold of Pain
140dBA - Military Jet takeoff/Gunshot (close range)
The reference card can generate a lot of noise under load, especially when running Furmark, with the small fan spinning at an incredible rate. The Arctic Accelero Twin Turbo 6990 on the other hand has a dual 120mm fan system and therefore they can spin much slower, while generating significantly better air flow. At 1,500 rpm the noise levels peak at just over 33 dBa, barely audible in a performance gaming system. Fantastic results.