The power grid
Read the situation and the numbers it starts from, then pick the change you would make. Every option was run, so the answer comes from the measurement rather than from anyone's judgement, and after you choose you see what all of them did. Progress is stored in this browser.
All 3 situations in this kind, with their tables
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Which change brings the drop down the most?Leave it, it is well under one percent: 0.6 · Put the grid back: 0.38 · Halve the clock frequency: 0.39 · Spread the design out: 0.62
Restoring the grid is the direct fix and the best one, and it costs nothing measurable in power, area or wire. Halving the frequency gets almost the same drop by a different route: half the switching is half the current, and it is a lot to give up for a tie. Spreading the design out makes it slightly worse rather than better, because the current then travels further through straps that are already too thin, and it pays 12 percent more wire for the privilege. When the metal is the problem, only metal fixes it.
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Which change brings the drop down the most?Keep the thinned grid: 8.82 · Put the grid back: 0.83 · Halve the clock frequency: 4.37 · Spread the design out: 7.42
Same four choices as on the small block, same winner, and a completely different outcome, because here only one of them works. Putting the grid back takes the drop from 8.82 percent to 0.83. Halving the frequency halves the power and only halves the drop, leaving 4.37 percent, which is still a broken supply bought at the price of half the performance. Spreading the design leaves 7.42. And the thinning never bought what it was for: the routing resource in use fell from 29.04 percent to 28.66 and the wire got 130 micrometres shorter out of 262811. The trade that sounded like a trade was ten times the voltage drop for nothing.
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Which change brings the drop down the most?Leave it: 6.9 · Double the strap density: 2.38 · Halve the clock frequency: 3.19 · Spread the design out: 4.42
Doubling the straps takes the drop from 6.9 percent to 2.38 and changes nothing else measurable: power, wire and timing all stay within a fraction of a percent. Halving the clock comes second, at 3.19, and gets there by removing more than half the power, which is a real achievement bought with half the performance. Spreading the design out is the worst fix of the three: 14 percent more wire for a drop still above 4 percent. The platform's grid is sized for a typical block, and a block drawing half a watt is not typical. When the drop is the problem, metal is the cheap answer, again.