Despite the attractiveness of power supplies that meet the requirements of 80 Plus Gold, the «bronze» solutions are still the most popular. The reason for this is the banal high cost of energy-efficient devices. Although there is still a downward trend in prices, although not as much as we would like. If you look at the prices of the 80 Plus Bronze models, the latter have become so affordable that there is simply no point in purchasing conventional solutions.
As for the power of power supplies in general, for a mid-range gaming system it is quite possible to limit yourself to a 450-500 W device, while for a more productive one you will need 550-650 W solutions. One thing can be said about configurations with a pair of video cards operating in CrossFire or SLI modes — at least 700 watts for mid-range accelerators, while already powerful cards will require 900 watts and more, and preferably a «gold» version to reduce system power consumption.
Considering the popularity of mid-range gaming systems, we will consider a 700-watt solution from Gigabyte.
Another model announced this winter together with the GP-G750H. Like the solution discussed earlier, our GP-B700H also has a modular design, but unlike the first one, it only meets the 80 Plus Bronze certification, i.e. has a maximum of 85% efficiency.
The block comes in a box made in black and orange colors, on the back of which the main characteristics of the product, cables and key features of the novelty are painted.
The kit is already familiar from the older model and includes instructions, mounting screws, Velcro straps with the company logo, a set of detachable cables and a bag for storing them, as well as a network cable.
The main cables for powering the motherboard and processor are not detachable, their length is 50 and 61 cm, respectively. The rest of the cables are:
- two double with 8-pin (6 + 2) connectors for powering PCI-E video cards (50 cm);
- one with four power connectors for SATA devices (55+15+15+15 cm);
- two with three power connectors for SATA devices (55+15+15 cm);
- one with three power connectors for IDE devices and one FDD (55+15+15+14.5 cm).
Flat cables are now fashionable, but they are very rigid and sometimes it will not be so easy to lay them when assembling the system.
Externally, the block is made at the proper level. The black case and wire grille are the hallmark of modern devices.
On the inner panel there are connectors for detachable cables, all of them are signed and have a different size, so it will be impossible to confuse which one to connect to.
As it should be in a modern device, the GP-B700H has one +12V line, which can provide up to 648 watts of load, and this is almost the rating of the unit itself. On low voltage channels, the combined power is only 130 watts, but this is enough by today’s standards.
The standby mode can count on 2.5 A, and for the –12V line, the developer has provided 0.3 A.
|Max. load current, A||22||18||54||0,3||2,5|
|Combined power, W||130||648||3,6||12,5|
|Total maximum power, W||700|
There is an active PFC and the ability to work in the entire range of mains voltage. Of the protections, they are present from power overload, over and under voltage, short circuit.
But enthusiasts are least interested in the appearance of the power supply — the main thing here is what’s inside. So, we remove the cover and see a very common CWT platform, made on Schottky diodes with group voltage stabilization.
The number of elements has been reduced to a minimum, but this is not surprising, given how much time has passed since the appearance of the first «bronze» solutions. In almost 10 years, the platform has been honed and now it remains to wait for a complete transition to more energy-efficient devices.
Despite the small number of parts, the inlet filter is up to the mark and almost all components are filled with glue.
The block is controlled by a pair of microcircuits. This is the CM6800TX chip, which ensures the operation of the active PFC and the power section, and the TNY177PN controller, which is responsible for the standby voltage. For monitoring, a Sitronix ST9S313-DAG chip (aka SiTI PS113) was used.
The power elements in the input circuit are cooled by a thick aluminum plate with small fins. The same is in the buck converter. In addition, a small L-shaped plate is provided for the diode bridge in the high voltage circuit.
The presence of Nippon Chemi-Con’s 390uF and 400V capacitance is encouraging, but CapXon, Su’scon and even Jun Fu are in the rest of the circuits. With such a “collective”, it will be necessary to increase the purge of the block to ensure an acceptable temperature regime.
The board for connecting cables is the same as that of the “golden” Gigabyte solution, discussed earlier. No containers are provided here, it performs only transit functions.
In the GP-B700H, a strange connection of wires using crimps attracts attention. Fortunately, they are designed to control the unit and have nothing to do with the supply circuits.
Otherwise, there are no complaints, the soldering is good, no washed flux, no “snot” were found on the board.
The unit is cooled by a 120mm Ong Hua HA1225H12B-Z fan with a two-pin connection.
At system startup and idle, it spins at 990 rpm, which rises only a couple of dozen revolutions under normal gaming load. If the power taken off is brought almost to the nominal value, its speed will already be 1500 rpm. Naturally, the noise level will be high.
It is difficult to conduct a full test without an appropriate stand, so the power supply was tested using a conventional system assembled from the following components:
- processor: Intel Core i7-6700K (email@example.com GHz);
- motherboard: ASUS Maximus VIII Impact (Intel Z170);
- Cooler: Prolimatech Megahalems;
- RAM: HyperX HX430C15PB3K2/16 (2×8 GB, DDR4-3000, 15-16-16-35-1T);
- video cards: Gigabyte GV-N770OC-2GD (GeForce GTX 770);
- drive: Kingston SSDNow UV400 240GB (240 GB, SATA 6Gb/s).
Testing was carried out in the Windows 10 x64 environment on an open stand. To create the maximum load on the system, the LinX 0.6.5 and FurMark 1.17.0 utilities were simultaneously launched for 30 minutes, and the Valley benchmark acted as a gaming benchmark.
The increase in load required us to use our old configuration:
- processor: Intel Core i7-975 (firstname.lastname@example.org GHz, Bclk 175 MHz);
- motherboard: ASUS P6T7 WS SuperComputer (Intel X58);
- cooler: Noctua NH-D14;
- RAM: Kingston KHX2000C8D3T1K3/6GX (3×2 GB, DDR3-2000@1750, 8-8-8-24);
- video cards: ASUS ENGTX295/2DI/1792MD3/A and Inno3D GeForce GTX 295 Platinum Edition (GeForce GTX 295);
- hard disk: Samsung HD502HJ (500 GB, 7200 rpm, SATA-II).
Here testing was carried out in the Windows 7 x64 HP environment on an open stand. To create the maximum load on the system, the OCCT 3.1.0 utility was used with a 30-minute power supply test in windowed mode with a resolution of 640×480 pixels.
The Basetech Cost Control 3000 was used to measure the total power consumption of the system, also capable of displaying peak power, current, mains frequency, power factor, etc. on its LCD screen. possible efficiency of the device. Errors in such calculations can be 5%. The voltages were checked with a UNI-T UT70D digital multimeter.
In addition, we decided to slightly expand testing by taking temperature readings inside the power supply, fan speed and noise level under a particular load.
The temperature was measured using the Scythe Kaze Master Pro panel, the sensors of which were located on the radiators inside the block and at a distance of 1 cm in front of the fan (#1) and behind the outer wall (#2).
For fan speed results, a UNI-T UT372 non-contact tachometer was used. The maximum speed was fixed for each of the power supply testing modes.
The noise level was measured with a UNI-T UT352 sound level meter in a typical quiet room at a distance of 1, 0.5, 0.1 and 0.01 m from the device under test. With the help of a speed controller and a tachometer, the fan speed was restored, corresponding to each mode of testing the power supply. Background noise did not exceed 33.4 dBA.
It should be borne in mind that such a technique at this stage is far from ideal and will be supplemented and changed as it is used.
The obtained data are entered in the table. In brackets for voltage are percent deviations from the norm, for power consumption — the approximate net load on the power supply.
|GTX 770||GTX 770||GTX 770||GTX295+GTX295|
|Mode||Idle||Burn, Game||Burn, Max||Burn, OCCT|
|Power consumption, W||46 (~36)||289 (~250)||407 (~345)||758 (~625)|
|Line +3.3V, V||3,33 (+1,1)||3,33 (+1,1)||3,33 (+1,1)||3,37 (+2,1)|
|Line +5V, V||5,07 (+1,4)||5,12 (+2,4)||5,12 (+2,4)||5,08 (+1,6)|
|Line +12V1 (MB), V||12,04 (+0,3)||11,76 (–2)||11,73 (–2,3)||11,78 (–1,8)|
|Line +12V2 (CPU), V||12,04 (+0,3)||11,78 (–1,8)||11,73 (–2,3)||11,78 (–1,8)|
|Line +12V3 (VGA1), V||12,04 (+0,3)||11,74 (–2,2)||11,71 (–2,4)||11,75 (–2,1)|
|Line +12V4 (VGA2), V||12,04 (+0,3)||11,74 (–2,2)||11,71 (–2,4)||11,84 (–1,3)|
|Fan rotation speed, rpm||990||1004||1004||1453|
|Noise level, dBA (1 m)||34,2||34,3||34,3||37|
|Noise level, dBA (50 cm)||34,4||34,5||34,5||38,7|
|Noise level, dBA (10 cm)||39,1||39,4||39,4||49,2|
|Noise level, dBA (1 cm)||46,3||46,9||46,9||56,5|
|Thermosensor No. 1||26,6||26,5||26,5||26,5|
|Thermosensor No. 3||32,8||37,9||40,9||51,5|
|Thermosensor No. 4||40,1||47||53,1||71,4|
|Thermosensor No. 5||33,3||46,5||54,3||79,3|
So, judging by the results, the block based on the “bronze” CWT platform did not show anything new. The voltage drop on the +12-volt line is almost 2.5%, which is probably within the normal range. If you look at the readings of a temperature sensor mounted on a heatsink with output diodes, it becomes clear why the manufacturer used such a high-speed fan.
The reviewed Gigabyte GP-B700H power supply is of high quality, has a decent package, and will look good in a modern gaming system. Its power is enough even to use a bunch of a pair of mid-range video cards in CrossFire or SLI mode. The noise of the cooling system is a bit big, but against the background of such a tandem, it will no longer be so noticeable. The only thing is that this model has enough competitors on the market and the user’s choice may be partly based on sympathy for the Gigabyte brand.