I need more memory. I mean personally, not in my PC - I cannot remember
anything. Can someone remind me of the formula to calculate the thermal heat
output of a CPU given its voltage, frequency etc. I know I had it writte
down somewhere, but I can't remember where I put it.
It involves squaring the voltage and multiplying by the frequency and some
other bits, but the order and extra bits in the formula escape me...
Thanks.
Yes, square the voltage an multiply the frequency. The part
you're leaving out is that each CPU core design is another
variable. You would backwards solve for that variable per
each CPU core. Even better would be to solve for several
models in the same family around the targets or average thm
all, but for the sake of simplicity (to get a near-enough
ballpark figure),
X = W/ [(Freq)*(V)²]
Probably the generic equation you wanted. Plugging some
numbers into that to determine the specific CPU core design
constant, let's consider a hypothetic CPU with the following
specs:
CPU "X" with 100W @ 3000 MHz & 1.5V, default spec.
Putting that into above equation we get,
X = 100 / [3000 * (1.5)²
X * 3000 * (1.5)² = 100
X = 0.0148
So if that CPU were at 2.0V but same Freq. we take same
equation as above to find wattage (but only for that same
specific CPU core with the 0.0148 value).
X = W/ [(Freq)*(V)²]
0.0148=W / [3000 * (2)²]
W= 0.0148 * 3000 * 4
Or if that CPU were at 1.5V default but o'c to 4GHz Freq,
0.0148 = W / [4000 * (1.5)²]
W = 0.0148 * 4000 * 2.25
W = 133.2
(should be 133.33 actually but we encounter a margin of
error because that 0.0148 variable was rounded off, was more
like 0.0148148148148/etc). Similarly all the variables have
a margin of error, your core voltage won't be spot-on
1.5000V nor bus frequency exactly same, etc,
