Factual error: When they first power-up the Stargate in the military facility (using Jackson's decryption), the thing surges to life, and electrical sparks spray out of overloaded connections all around the control room. This could only happen if there were no fuses or electrical breakers in the military's control system, which is a ridiculous notion for such advanced military technology. In real life, a powerful overload situation would instantly burn out fuses and trip breakers and the whole system would simply go dead (there would be no sparks). Showers of sparks are a common error in many science fiction and space fantasy films dating back many decades.
Suggested correction: If there would be breakers and fuses then yes, the system would simply go dead and then they would have nothing. They intentionally let the system nearly overload because without power they wouldn't be able to finish the sequence.
No, that's not the way sophisticated (and expensive) electronic technology works. If you have sparks spraying out of electrical connectors, that means you're melting down millions and millions of dollars of hardware. No technician or electrician or even a first-year auto mechanic would intentionally design and hardwire an electrical system without fuses and/or breakers.
They're dealing with Ancient technology. It's quiet possible that such an advanced piece of technology as a Stargate could cause powerful arcs of electricity along lines separated even by tripped breakers.
Ancient technology does not override electrical physics. Modern electrical equipment is protected with fuses and breakers for a reason. If the Stargate technology overrode the parameters of the modern equipment, it would melt down the modern components being protected by the fuses and breakers. Either way, the whole system would shut down.
Factual error: When the USAF car arrives to speak to O'Neil, the car has a GSA (Government Services Administration) license plate on the front. As you see the door open, the printing states an Air Force Registration Number, meaning this vehicle does not require a GSA tag and should have a license plate with the letters USAF.
Revealing mistake: Right after O'Neil and Jackson are captured inside the pyramid and taken aboard the alien ship a distant shot is shown of the ship while it is opening. In the sky over the ship are depictions of three moons. Each of the three moons shown in the sky of the distant planet are actually the Earth's moon when it is full but just shown rotated slightly in different positions. (01:38:00)
Continuity mistake: The pen used in the beginning of the drawing is different from the solid blue one used in the close up shot. Also, when the camera goes back to a wide shot, the color of the drawing on the whiteboard changes from blue to black. (00:17:40 - 00:18:35)
Continuity mistake: RA continues to wear the necklace at the end of the movie when it was taken from him by Daniel before he left the spaceship via the transporter.
Revealing mistake: On the first night at the slaves' fortress, Daniel is eating the "chicken" and telling them how good it is. After that they take him away to give him a wash. As they walk off, they pass the small fire the slaves have made. If you look at the fire closely, there is a metal circle at the bottom and the fire is coming out of seven holes in it, which means that it is a prop gas fire.
Other mistake: When one of Jackson's crew raises his 35mm camera and takes a picture, there's no lens on the camera.
Other mistake: When the ship lands atop the pyramid and begins to retract and open the topmost sections of the pyramid retract into the lower parts however the upper parts are too long to fit into them. In the next sequence we see the ship and the upper parts are nowhere to be seen.
Suggested correction: Perhaps the parts fold further in on themselves. Like a retractable ladder.