An important tip from one of our users: don't just check total power output, find out what you need in the way of current on each power rail. If you need 20 A on your +12V rails and the supply only has 15A, it doesn't matter how many watts the supply puts out: don't buy it. Make certain that you have ENOUGH rails, too: sometimes, you need more than just two +12V rails for your setup.
Replacing an existing power supply is easier: just get a replacement that meets or exceeds the specifications of the old one. (You can usually find those printed on the side of the supply.)
That said, here's a power supply that is compatible with most ATX format motherboards, puts out 430 watts of power (see specifications for exact distribution). Could this be your next power supply?
ATX12V v2.2 CompatibleCompatible with the ATX12V v2.2 standard, the Antec True Power Trio TP3-430 power supply provides maximum power stability to drive the latest Intel and AMD processors as well as other system components.
430W Maximum PowerThe Antec True Power Trio TP3-430 provides a maximum power of 430W to deliver safe, reliable output for high-end computer systems.
Highly EfficientProviding up to 85% power efficiency, the Antec True Power Trio TP3-430 power supply saves energy and may even reduce your electric bill!
Efficient CoolingA low-noise 120mm fan delivers highly efficient cooling for the power supply and the whole system and ensures quiet operation.
Special Fan-Only Power ConnectorsThe Antec True Power Trio TP3-430 power supply features Fan-Only power connectors to control case fan speeds for overall reduced system noise.
Learn more about the Antec TP3-430
General
Brand
Antec
Series
True Power Trio
Model
TP3-430
Details
Type
ATX12V
Maximum Power
430 W
Fans
1 x 120mm low noise cooling fan
PFC
Active
Main Connector
20+4Pin
+12V Rails
Three 12V output circuits provide added system stability
ATX12V version 2.2 Universal Input, automatically adjusts for 100V to 240V power grids Active Power Factor Correction (PFC) for environmentally friendlier power Accurate power rating allows TruePower Trio to deliver its full rated power, 24 hours a day rated at 50°C Fan only power connectors allow TruePower Trio to control case fan speeds, reducing total system noise Dedicated outputs for stable output and less ripple noise Feedback loop circuits for tighter load regulation (±3%) to maintain accurate voltage to all components Heavy duty protection circuitry prevents damage resulting from short circuits (SCP), power overloads (OPP), over voltages (OVP), and under voltages (UVP) Power Factor value up to 99% Gold plated connectors for superior conductivity AQ3 – Antec Quality three-year parts and labor warranty