Acer 3800 is a 2.4 GHz Anyone else think the name changes are deceptive?

  • Thread starter Thread starter Terry
  • Start date Start date
T

Terry

I asked a friend who just bought a new computer how fast it was.
After looking at the instructions it turns out a 3800 is a 2.4.
 
In alt.comp.hardware.pc-homebuilt Terry said:
I asked a friend who just bought a new computer how fast it was.
After looking at the instructions it turns out a 3800 is a 2.4.
Click to expand...

That's probably an AMD 3800, that supposedly "runs as fast as" an Intel
at 2.4ghz. The reason is the internal clock and instruction-cycle and
how fast the CPU actually executes instructions has little to do with
the external (or often even internal) clock-speed. The Intel devices
tend to do less per-clock-cycle than AMD does; thus allowing AMD to do
things under less pressure; but leaving it behind in the specification
wars where some people ass-u-me that a processor with a faster internal
clock-rate will necessarily run programs that much faster. It ain't so.

SOOOOO ... AMD cheats and calls its machine a 3800 because it executes
most Pentium instructions about as fast as a 3.8ghz Intel device; even
though its internal clock-rate is only 2.4ghz.

Get it?
Run one of each side-by-side doing the same job, and you would.
Sometimes, in such a race, the Intel device *will* actually be faster.
Others, not; or the other way around. It really depends on what job you
feed each one; as not all jobs are equal.
 
I asked a friend who just bought a new computer how fast it was.
After looking at the instructions it turns out a 3800 is a 2.4.
Click to expand...
And? It's been a common naming system used by AMD since the 90's where
it refers to the performance equivalence rather than the clock speed.

Clock speed hasn't been a reliable indicator of performance for years.
 
Conor said:
And? It's been a common naming system used by AMD since the 90's where
it refers to the performance equivalence rather than the clock speed.

Clock speed hasn't been a reliable indicator of performance for years.
Click to expand...

Roughly speaking:

Performance = Clock_Speed x Instructions_Per_Clock_Cycle

Since AMD had a larger Instructions_Per_Clock_Cycle, by a factor
of about 1.5x or so, they were always losing out in clock speed
comparisons. So AMD made up their "P.R. rating" system, to counteract
that trend. The P.R rating, is a way of quoting the "effective"
speed of the processor (i.e. when compared to Intel P4), and
helps take into account the superior Instructions_Per_Clock_Cycle.

Now that Core2 Duo processors exist, they have the very same problem.
The new Intel design has also managed to boost Instructions_Per_Clock_Cycle.
A new Core2 Duo at 2GHz, is roughly equivalent in integer performance,
to maybe a 3.2-3.4GHz Pentium 4 processor. So you cannot compare
the clock speeds of families of processor directly, and need some
way to measure the parallelism (Instructions_Per_Clock_Cycle)
as well.

I find the best way, is to view various benchmarks, to see the
apparent advantage.

Paul
 
The general object is to thoroughly research your intended purchase BEFORE
you hand them the money...
 
Back
Top