300 Watt ATX Replacement Computer PC Power Supply

Replace or upgrade to a 300W power supply for a standard ATX computer

Product ID: ATXPOWER300

  • Provides a maximum output power of 300 watts
  • High-Flow fan provides efficient cooling for the system and power supply
  • High quality connectors provide minimal resistance and enhanced electric conductivity
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  • Premium EMI/RFI power filtration system provides low noise/ripple for super clean and stable power to all system components
  • ATX version 2.03 and ATX12V compliant
  • 2 years warranty
  • Quad Protection Plus: Short Circuit Protection, Over Voltage Protection, Over Load Protection, Over Current Protection, and No Load Operation.
  • Long-life transformer and built-in short-circuit protection
  • The temperature controlled smart fan cools your entire system while the EMI/RFI power filter reduces noise/ripple
$72.99 CDN
1324+ In stock
In stock
CA: 167 | US: 1157
In stock
Where To Buy


A reliable upgrade or replacement power supply for desktop PCs.

This power supply offers an upgrade or replacement to a variety of Intel or AMD-based ATX desktop computer systems. Compliant with the industry standard ATX specification and using the standard ATX form-factor, this power supply (PSU) can be used as a replacement in a variety of popular OEM desktop systems.

Conforming to ATX revision 2.03, this power supply features a 20-pin ATX power connector and 6-pin AUX power connector, for support for older, legacy computer systems, as well as some newer, low powered systems with it's ATX12V connector. High quality components and a built in 80mm cooling fan lend to a durable and reliable power supply, while being backed by's 2 year warranty and free lifetime technical support.

The Advantage

  • High performance components and connectors are designed for extra long life and provide maximum system performance
  • Long-life transformer and built-in short-circuit protection
  • See Applications page for detailed list of supported
  • The temperature controlled smart fan cools your entire system while the EMI/RFI power filter reduces noise/ripple


Replacement for standard 250W & 300W ATX12V Power Supplies

Replacement Power Supply for Bestec ATX-300-12E

Compatible with following eMachines A-Series Model:

Compatible with following eMachines C-Series Models:
C1641, C1844, C1904, C2160, C2280, C2480, C2684, C2685, C2782, C2825

Compatible with following eMachines D-Series Models:
D2046, D2244, D2246, D2266, D2346, D2386, D2586, D2685

Compatible with following eMachines H-Series Models:
H2341, H2482, H2542, H2602, H2615, H2642, H2742, H2825, H2865

Compatible with following eMachines S-Series Models:
S1642, S1862, S1940, S2482, S2485

Compatible with following eMachines W-Series Models:
W1500, W1640, W1700, W1800, W2040, W2047, W2060, W2247, W2060, W2247, W2260, W2646, W2686, W2785, W2958, W4682, W4065

Compatible with following eMachines T-Series Models:
T1140, T1150, T1220, T1221, T1300, T1360, T1440, T1600, T1740, T1742, T1782, T1840, T1842, T1860, T1862, T1980, T2040, T2042, T2080, T2082, T2085

T-Series (cont'd):
T2200, T2200SE, T2240, T2245, T2260, T2341, T2385, T2460, T2482, T2484, T2542, T2596, T2605, T2615, T2625, T2642

More T-Series:
T2672, T2682, T2692, T2698, T2778, T2792, T2796, T2798, T2824, T2825, T2842, T2865, T2875, T2882, T2885, T2895, T3025, T3265, T4060, T4080, T4170, T4480, T4510, T4511, T4697, T6000

Compatible with following Gateway Models:
DX100, B330

Technical Specifications

Warranty Information
Warranty 2 Years
Fan Bearing Type Sleeve Bearing
Fans 1 - 80 mm
Air Flow Rate 32.3 CFM
Efficiency Rating >65% (Typical Load)
Fan RPM 3000 RPM +/-10%
MTBF 40,000 Hrs
Noise Level 27.4 dBa
Output Power 300W
Power Factor Correction No
Output Connectors 1 - ATX 12V P4 Power (4 pin, v 2.x) Male
1 - ATX AUX Power (6 pin, v 1.x) Female
1 - ATX Power (20 pin, v 1.x) Male
1 - SATA Power (15 pin) Receptacle
2 - SP4 (4 pin, Small Drive Power) Female
6 - LP4 (4 pin, Molex Large Drive Power) Female
Current +12.0V1 (A) 15A
Current +3.3V (A) 28A
Current +5.0V (A) 30A
Current +5.0Vsb (A) 2A
Current -12.0V (A) 0.8A
Current -5.0V (A) 0.3A
Input Current 8A ~ 4A
Input Voltage 115~230
Max Inrush Current 50
Operating Temperature 0 ~ 50
Storage Temperature -20 ~ 80
Physical Characteristics
Product Height 3.3 in [8.5 cm]
Product Length 5.9 in [15 cm]
Product Weight 4.1 lb [1.9 kg]
Product Width 5.9 in [14.9 cm]
Packaging Information
Shipping (Package) Weight 4.3 lb [2 kg]
What's in the Box
Included in Package 1 - 300W ATX Power Supply
1 - Power Cord (NA)
1 - Instruction Manual



Product Support

Frequently Asked Questions

Before You Buy

There are a few factors to look at when deciding on an appropriate power supply for your computer. These will be outlined below.

Form factor offers ATX form factor power supplies.  This form factor is suitable for regular desktop computers.  These will not fit in smaller desktop computer cases that require mini or micro ATX form factors, such as slim line computers.  It is important to verify if your computer case and motherboard use the ATX form factor. Refer to the information provided by the manufacturer to confirm which standard you require

Power output

The power supply that you choose should be able to output enough power for all of your components, even under a very high load. The power output of power supplies can range from 200 to 1800 watts (for very high end products), but the most common power supply outputs are 300 to 500 watts. It is recommended to replace a power supply with one that can output at least the same amount of power.

Available connections

It is important to verify that the power supply has enough connections, and the appropriate type of connections for all of the components in your system. It is recommended you at least check for the most common types of connections, listed below:

  • ATX Split Power (20+4 pin) Male
  • ATX 12V P4 Power (4 pin) Male
  • LP4 (4 pin, Molex Large Drive Power)
  • SP4 (4 pin, Small Drive Power)
  • SATA Power (15 pin)

Your video card may also require one or two PCI Express Power 6 or 8 pin connectors.  Check your computer to see which connections, and how many of each you need. lists which connections a power supply provides on each product page under the Technical Specifications tab.

300 Watt ATX Replacement Computer PC Power Supply

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