A Closer Look
The BFG Tech 600W power supply enclosure appears to be nickel plated and uses a single 80mm exhaust fan on the back for cooling. The fan speed is automatically controlled by the internal component temperature (speeds up as the combined load and temperature increases). The power supply incorporates universal input (automatically adjusts the AC line voltage) and active PFC that adds to the units environmental friendliness.
Slotted openings on the front allow air to enter the power supply for cooling.
The BFG Tech 600W power supply supports ATX12V v2.01 and is rated for a combined, maximum output power of 600 watts. The PSU includes universal input with active PFC and provides two separate +12V outputs, each rated for up to 20A.
Dual +12V outputs
The BFG Tech 600W PSU incorporates two 12V outputs (+12V1 and +12V2). The following table shows the maximum rated current and what connectors are supplied by each output.
Note: The maximum combined load for the +12V1 and +12V2 outputs is 39A.
Most typical users have little idea about the true power requirements of their particular system. It might come as a surprise that the majority of modern PC’s actually use less than 200 watts of power (75% efficiency x 200 watts AC in = approximately 150 watts DC load). For example: I used a WattsUp? Pro power meter to measure the AC power consumption during idle, CPU load, and gaming conditions of a typical PC consisting of the following components.
- Epox EP-9NPA nForce4 Ultra motherboard
- Athlon 64 3200+ (90nm) CPU
- (2) Corsair 512 MB XMS 3200XL low latency RAM (2-2-2-5)
- Leadtek GF6600GT PCI-e 128 MB video card
- Western Digital 120MB Serial ATA HDD
- Sony 16X DVD DDU1612
- Panasonic DVD/CD Writer DVR-108 dual layer
- FDD and Universal card reader
- (2) 120mm low-speed cooling fans
System idle (sitting at Windows XP desktop) 112 watts
CPU full load (Folding@Home) 139 watts
Gaming benchmarks (3Dmark) 158 watts
I also measured the current flow going to the motherboard thru the +3.3V, +5V, +12V main and +12V aux lines with a FLUKE ammeter.
So why then you might ask, would we need a 500W or 600W power supply? For one thing a power supply should ideally be rated for approximately twice the expected maximum load. If your PC will use between 150~200 watts of DC power then the PSU should be rated for at least 350~400 watts. This will allow the power supply to operate at around 50% of its rated capacity.
And if you are a gamer with one or more high-end video cards, then you will definitely need a high-quality, larger capacity power supply! BFG Tech recommends using a minimum 400W power supply (12V current rating of 26A or more) with their GeForce 7800 video card. If you have two GeForce 7800’s in SLI mode, then a minimum 500W power supply (12V rating of 34A) is recommended. Remember, the maximum combined load for the BFG Tech 600W power supply’s +12V outputs is 39A, so we should be good to go.
The BFG Tech 600W power supply has a full assortment of cables and connectors. The main wiring harnesses measure approximately 25′ long to the first connector and only the main 24-pin power cable is covered with black plastic mesh sleeving.
- Main power connector (24-pin/20-pin)
- ATX P4 12V (4-pin)
- (2) PCI Express (6-pin)
- (8) Peripheral Optical/HDD (4-pin)
- (3) Peripheral FDD (4-pin)
- (2) Serial ATA (15-pin)
The main motherboard connector uses the newer style 24-pin connector that is designed to permit removing the extra four pins so no adapter cable is required when plugging into a 20-pin connector.
Here are a few pictures showing the layout and components inside the BFG Tech 600W power supply. Multiple printed circuit boards are stacked in various locations to allow for good airflow and cooling.
