Cons: Not enough available power for top of the line video cards
A-DATA 4GB DDR2 800 RAM
AMD Athlon 64 X2 7750 2.7GHz Processor
Antec 300 Case
Antec EarthWatts EA650 PSU
ASRock A780GXE/128M AM2+ 780G ATX Motherboard
LG 22X SATA DVD+R DVD Burner
SAPPHIRE Radeon HD 4830 512MB Video Card
Western Digital Caviar Black 500GB Hard Drives (2)
When I originally built this system, I wanted to make sure I had plenty of power available for possible future upgrades. If your power supply isn't up to the task your system could be unstable, not power up, or you could randomly have system freezes or reboots. Not a good thing if you rely on your computer at all. The Antec EarthWatts EA650 PSU (Power Supply Unit) has plenty of power for the modest needs of this system.
The quality of the power supply is arguably even more important than the total power however. I had another system I had built a couple years before, and when it's cheap power supply failed it sparked and whistled and let forth a plume of thick white smoke that reeked of fried circuitry. It didn't manage to destroy any of the other components in the process, but it very well could have.
Antec is a pretty big name when it comes to certain computer components such as power supplies and system cases. When I built this computer I purchased an Antec 300 Case and this Antec EarthWatts 650W PSU at the same time along with the other components. I really don't like power supplies that come pre-installed in cases because they're usually cheap and inadequate and I end up tossing them to replace them with a better product anyway. That's why I purchased a case and power supply separately, so I knew what I was getting and wouldn't have to replace it a month down the road.
I usually prefer my power supplies to have a single 12V rail with a lot of amps available on it. My Corsair CX600 for example supplies 40 amps of power on its single 12V rail. The rails are just different lines of power output, and most of the components in your computer will be drawing 12V of power. Splitting the 12V among three rails means lesser amps on each one, and I've seen some power supplies that can only give 16 or 17 amps on a rail. This is the reason I often prefer a single rail over a multi rail solution. This Antec EarthWatts EA650 has three separate 12V rails and it outputs 22A on the first, 22A on the second and 25A on the third. This is the maximum amperage for each rail separately, but it also has a maximum combined output of 540W across the three rails.
The Antec EarthWatts EA650 has an 80 PLUS Certification, meaning it's more efficient and better for the environment than a PSU that does not have this certification. In order to be 80 PLUS Certified, a power supply has to operate with at least 80% efficiency at 20% load (light duty), 50% load (average duty) and 100% load (heavy duty). Note that this only has the regular certification and not the Bronze, Silver, Gold or Platinum levels that are a few percent more efficient.
1x 24 Pin ATX/Main
1x 4 Pin ATX/12V
1x 8 Pin EPS/CPU
2x PCI-E (6 Pin and 6+2 Pin)
The 8 pin EPS/CPU and the 4 pin ATX/12V connector are alone on the first 12V rail (12V1), making sure you maintain ample power to run your faster multi-core processors. The second rail (12V2) contains the main 24 pin ATX connector, the 6 molex/peripheral connectors, the single floppy connector and the 6 SATA connectors. Hard drives and optical drives aren't going to draw more than a couple amps each, so this is sufficient for all but the most overloaded of systems. The third 12V rail (12V3) is dedicated to the video card, containing the 6 pin PCI Express connector and the 6+2 pin PCI Express connector. Overall, the layout of the rails and the amount of amperage available on each one seems pretty well balanced and nicely laid out.
The only downside to this is that it limits your ability to install higher end graphics cards, especially in an SLI/Crossfire setup. The available 25 amps is just sufficient for the Radeon 4830 that is in the system now, or I could swap in a Radeon 6850 or a GeForce GTS 450 - but swapping in a Radeon 6950 or a GeForce GTX 465 instead would be out of the question, requiring about 30 amps of power. This also means that despite the dual PCI Express connectors, you're not going to be able to run much in SLI/Crossfire mode, as there just wouldn't be enough available power. It's nice for those few graphics cards in the sweet spot that require about 25 amps or less and require two PCI Express connectors, but still, this power supply is inadequate for heavy gaming and top of the line graphics cards.
The wires were a little on the short side, but they reached everything in my case with no issues. I wish they were a little longer so that I could route them a little better instead of leaving them stretched across the middle of my system, but I expected this from a budget priced power supply. Only the main 24 pin ATX connector has a sleeve wrapped around the wires coming from the PSU, while the other cables are just plain wires. The connector ends of each cable are firmly attached and fit snugly into their respective sockets, and the wires aren't a tangled mess like some power supplies have.
150mm wide, 86mm tall, 152mm long
0.99 Active Power Factor Correction
Maximum power: 650W continuous output
Universal input voltage from 120-240V
Output: +3.3V@25A, +5V@25A, +12V1@22A, +12V2@22A, +12V3@25A, -12V@0.5A, +5VSB@2.5A
MTBF (Mean Time Between Failures): > 100,000 hours
3 year warranty on parts and labor
The 120mm exhaust fan is pretty quiet, inaudible over the other components in this system. CPUID Hardware Monitor does not list the volts on the +12v rails like it does when I plug it into the other computer. Looking at the system BIOS, it shows 12.196 volts. I assume this is the average across all three rails, but I have no idea for sure. All I know is that the system has been rock solid and stable since I built it in April of 2009. The computer ran 24/7 for the first couple years of its life, and during the last year has been getting used just a few hours each day. I've been pretty happy with it, and I would recommend it to anyone as long as they don't plan on using a top of the line graphics card.