Review: Cooler Master ATCS 840 - The return of a legend?

by David Ross on 6 January 2009, 15:22 3.75

Tags: ATCS 840, Cooler Master, PC

Quick Link: HEXUS.net/qaqac

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Thermal results

System specification

HEXUS chassis test equipment specification
Motherboard eVGA 780i SLI FTW
Processor Intel Core 2 Extreme QX6850 3.00GHz, 1333MHz FSB
Memory 4GB (2 x 2GB) Corsair DDR2 PC8500
Memory timings and speed 5-5-5-18 2T @ 1,066MHz
Graphic card NVIDIA 8800 Ultra 768MB PCIe
Power supply Dark Power PRO 850W
Hard drive Seagate Barracuda 7200.7 160GB (ST3160812AS)
Optical drive Sony SATA DVD-RW

Thermal results

Load temperatures at the start of testing
Chassis HEXUS open test-bed Cooler Master ATCS 840
Ambient temperature 23.1 22.1
Case ambient temperature 24.1 27.4
Ambient to case ambient delta 1 5.3
CPU temperature 57 61
CPU to case ambient delta 32.9 33.6
CPU to ambient delta 33.9 38.9
GPU temperature 70 79
GPU to case ambient delta 45.9 51.6
GPU to ambient delta 46.9 56.9
MCP temperature 57 57
MCP to case ambient delta 32.9 29.6
MCP to ambient delta 33.9 34.9

Idle temperatures at the end of testing (After being under-load for 3 hours)
Chassis HEXUS open test-bed Cooler Master ATCS 840
Ambient temperature 24.5 23.1
Case ambient temperature 25.7 27.5
Ambient to case ambient delta 1.2 4.4
CPU temperature 48 56
CPU to case ambient delta 22.3 28.5
CPU to ambient delta 23.5 32.9
GPU temperature 68 72
GPU to case ambient delta 42.3 44.5
GPU to ambient delta 43.5 48.9
MCP temperature 57 57
MCP to case ambient delta 31.3 29.5
MCP to ambient delta 32.5 33.9

Load temperatures at the end of testing (3 hours under-load)
Chassis HEXUS open test-bed Cooler Master ATCS 840
Ambient temperature 24.5 23.1
Case ambient temperature 25.9 28.5
Ambient to case ambient delta 1.4 5.4
CPU temperature 58 68
CPU to case ambient delta 32.1 39.5
CPU to ambient delta 33.5 44.9
GPU temperature 84 88
GPU to case ambient delta 58.1 59.5
GPU to ambient delta 59.5 64.9
MCP temperature 57 57
MCP to case ambient delta 31.1 28.5
MCP to ambient delta 32.5 33.9

At the start the temperatures in the ATCS 840 are around five degrees warmer on the CPU and 10 degrees Celsius for the GPU.

The MCP (chipset) is effectively the same temperature on both platforms as the equipment is only accurate to within one-degree Celsius.

The temperature inside the chassis is pretty reasonable at just over four-degrees Celsius higher than the open test-bed.

After three hours' load (3x Prime95 + 3DMark06 @ 1,920x1,200 4xAA 16xAF), the difference has increased somewhat but is still pretty reasonable and none of the temperatures are alarmingly high.

The CPU temperature inside the ATCS 840 is now about 11 degrees Celsius warmer than the test-bed, whereas the GPU temperature difference has decreased and is down to a difference of around five-degrees Celsius.

You may be interested to know why the MCP temperature hasn't increased; the most likely explanation we can give is that it's down to the auto-fan-control for the MCP fan keeping it around that temperature.

On a chassis with inadequate ventilation in that area we'd expect it to increase by a couple of degrees as the fan struggles to keep it cool.

Looking at the idle temps one minute after it had been on load for three hours, it's clear that the heat build-up still hasn't subsided and the CPU and GPU temperatures inside the ATCS 840 are at the same amount higher than they were when under load.

This isn't surprising however as the case ambient temperature has hardly dropped.