The caps must be for the CPU core voltage, the tolerances are getting smaller
as the geometry shrinks. Current PowerPC chips are +/- 30mV in some cases.
That's really hard to hold when you have something like a FX55 chip that
burns nearly 100W at 1.2V core. it doesnt take much onboard or pin resistance
to drop 30mV at more than 50Amps IDD.
I predict that you will soon see switching power supplies mounted on the CPU
package to reduce the effects of contact resistance and lead inductance.
Either that or some 7/16" studs for Vcore and GND with some 00 gauge leads.
CPU packaging is going to have to change radically to handle 200W CPU die
with a 0.9V core which is what is predicted for 65nM geometry, 200Amps...
wow.. and the real killer is the current can change within nanoseconds
from 20% to 120% of max reated currrent. the 200W is an average.
instantaneous power can be much higher, maybe 2x. for a few clock cycles.
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