Brett (ggtgp.delete@this.yahoo.com) on March 26, 2021 4:39 pm wrote:
> wumpus (wumpus.delete@this.lost.in.a.hole) on March 26, 2021 9:10 am wrote:
> > Ganon (anon.delete@this.gmail.com) on March 25, 2021 5:56 pm wrote:
> > > My prediction for the immediate future is similar to what is happening today already.
> > > Not everyone buys the SKUs with the most core count: it would be silly to pay for >
> After the circuits are printed on the wafer the back it ground down as silicon is an insulator
> and the heat sink is on the back. The front is covered in solder balls for the socket.
>
> The old wire bound packages are the other way, but then you have a thick plastic insulator
> over your die. And CPU’s need to dissipate 150 watts off that tiny die.
>

You'd have to put all the connections through the vias. I/O shouldn't be an issue, but ~100A or more (average, don't know how high the peak bursts are, but considering they have to come from ceramic capacitors...) going through the vias is going to make or break the concept. Presumably long since broken, but vias on chips are coming back.

You'd also get to stick your heatsink right up against the ground plane, instead of going through the insulating silicon. This might well be the primary motivation for "de-flipping" chips (I think the "flip-chip" was the name they gave the modern package during the change Brett mentions).