Prime: Know it all?

Humans found the cube after they found Megatron. The cube was moved TO the Hoover Dam.

So Megatron basically effectively looked into the future to what the co-ordinates of the All Spark was GOING to be.

I don't know where you're getting that from, the cube has always been there, I think they flat out say it in the movie but I don't feel like popping it in to get the exact line.

Wot?

They found Megatron, then the Cube, then moved Megatron TO the Cube, then built the dam around the Cube. Where are you getting your info?

I think I can shed some light on this...

Judging by the prequel comic book:

Prime sent the Allspark to Earth. It landed where the Hoover Dam would eventually be built. It never changed location. Megatron memorized this location and headed right for it. Before Megatron reached the Allspark, he was caught in Earth's magnetic field (I assume "gravitational" field in the movie is a typo) and went into some kind of stasis lock.

While Megatron never physically got his hands on the Allspark, he did have the ability to shoot onto the glasses the last known location. For example, if the humans had moved the Allspark, then those glasses would've been worthless.

As for how Prime knows this and all that detail about the grandfather...

Shrug. Perhaps Unicron told him?

According to Wikipedia, "The All Spark is revealed to have landed on Earth, specifically in the Arctic Circle, and then subsequently moved to the future site of the Hoover Dam."

according to Wikipedia, the Allspark could've landed in care-a-lot, and been moved to South Park.

Wikipedia or the movie, novel and the animated prequel, which should I trust? Its Megatron who landed in the Artic Circle, not the Allspark.

Yeah. Wiki is wrong on that one (big suprise LOL). As most have already said, The AllSpark never moved once on earth, merely covered up by the Dam.

i dont remember where (i think it was the prequel) that the Cube did in fact move-to a small cave oe something for storage, then eventually brought back to (or close to) the original spot.

but yeah, Prime knowing details was probably stuff he figured out from the glasses and Bumblebee's scouting.

and, sadly, wikipedia is off a bit-that seems to be Megatron's moveabout story

no, i think they mean magnetic-basically, Megatron located the cube, but when he went in to retrieve it, the magnetic poles and whatnot of Earth messed with his systems like a magnet messes with a computer. it threw him wild, causing him to transform and land in the ice-since he was in robot mode, he didnt have the protection from cold his jet form did, thus freezing him.

and the reason the magnetic field didnt effect the Autobots is that Bumblebee probably had a similar issue that Megatron did, just landed somewhere else. then he warned the other autobots when they came to earth. OR maybe their Protoforms were specifically made to not be harmed by magnets, but Megatron didnt have that.