Can I give 12V DC to power inverter through PC Power supply?

Assuming you have a good reason for doing this, I'd check that the DC voltage input to the inverter from the PC supply doesn't exceed inverter input limits, within the range of the loads you are putting on the inverter output.

PC switching supplies may be persnickety about what load they are seeing.

inverter said:

I'm having a question whether i can give power to inverter using a PC power supply?
The Specification for the one i'm gonna use is provided below.
please advise me in this regard.
Specification:​

1200 Watt Continuous
2400 Watt Peak Surge
Model No.
PI-1200W-12V Continuous Output Power
1200W Max Output Power
2400W DC Input Voltage
DC 12V AC Output Voltage
230VAC/240VAC Regulation ±5% Frequency
50Hz±3% Efficiency
87% No Load current Draw
0.7A Output Wave Form
Modified Sine Wave Distortion
2% Temperature Protection
(55±5) Input Low Voltage Protection
YES Input Reverse Polarity
YES circuit protection
YES Output Short Circuit Protection
YES Overload Protection
YES

Click to expand...

Expect the total power available from a modern pc psu's 12volt rail to be about 200watts. If you use that to power an inverter expect ~150-175 watts available at the output of the inverter. If your load exceeds 200watts the pc psu will probably shut down.

A 500w pc psu I randomly selected at newegg provides [email protected]
That is 192 watts.

Another option for a large inverter like this is a car battery or deep cycle battery.

1200 watts @12 volts is 100 amps. Do you have a PC power supply capable of 100 amps or 200 amp peak?