Noise level
We measure the noise level by using noise
level meter CENTER-321 in a closed and quiet room about 20m2 large. The
noise measuring session is performed outside the case, where the only main
source that causes noise is from the cooling system and its fans. The noise
meter is mounted on a tripod and 15-centimeter far away from the fan rotor. The
motherboard, along with the graphics card is placed on the edge of the table
with a polyurethane foam sheet. The lowest reading the meter can read is 29.8
dBA and subjectively, the noise level in testing conditions from this distance
is 36 dBA (not low, acceptable). The graphics card rotational speed is changed
with the help of a special controller which is collative to the 0.5V voltage
increment.
Nvidia GeForce GTX 650 Ti, EVGA GeForce GTX
650 Ti SSC and 2 graphics card from ZOTAC don’t have the fan speed controller,
so we build a graph by extrapolating biggest fan speed (based on the technical
specs) to lower the voltage. Of course, it’s not a high-accurate way because the
correlation of speed between the fan speed and voltage is not linear one, but
we have no other method. Here are the results:
Diagram
showing the results of noise testing
Based on the diagram, GeForce GTX 640 and
GeForce GTX 650 Ti AMP! Edition of Zotac seems like the least noise-maker, but
we should also notice their fan speed in testing session. While Zotac GeForce
GTX 640 is actually quieter than the other 4, GeForce GTX 650 Ti AMP! Edition is
as loud as the graphics cards from Nvidia and EVGA, all of which seem to be
pretty inconvenient.
The Gigabyte WindForce 2X cooler runs at 1600
RPM speed at auto fan mode, so it’s quieter than others, including Zotac GeForce
GT 640. The product of Gigabyte is completely quiet at idle mode while Zotac
GeForce GT 640, as an example, creates sound that is audible at noise
conditions we tested.
Zotac
GeForce GT 640
Power consumption
We measure the power-consuming process of
the test equipped with different graphics cards by using the multifunctional
Zalman ZM-MFC3 panel, which is able to give detailed reports on how much power
it takes for the (without the monitor). There are 2 testing modes: 2D (edit the
documents in Microsoft Words or when surfing web) and 3D (running Metro 2033 3
times: The Last Refuge standards at 2,560x 1,440 at high image quality settings
and not using image anti-aliasing)
For the comparison purpose below, we also
add the results for MSI GeForce GTX 660 2 GB, Sappire Radeon HD 7850 2 GB and
AMD Radeon HD 7770 1 GB into the distribution table. Let’s see what we receive:
Power-consuming
process
As you can see, the configuration with 1
overclocked six-core CPU needs less than 400 watts regardless of graphics card.
It only needs 278 watts with GeForce GT 640. The products from Radeon consume
more power than their competitors, but not pretty much. The configuration with
different GeForce GTX 650 Ti graphic cards doesn’t differ much at electric
demand, but EVGA GeForce GTX 650 Ti SSC need more electrical energy than the Gigabyte.
We can see that the configuration of GeForce GTX 660 2GB needs 62 watts more than
GeForce GTX 650 Ti 1GB.
All configurations are comparable
considering power consumption in idle mode.
