(even though they are supposedly
measured differently) but most of
all it’s the exact same Asetek cooler
used for both.
Performance Analysis
If you were expecting to be blown
away, well you will not be. Very few
programs that we are concerned
with benefit from the additional
cache that this CPU has and the
rest are benefitting from the four
extra threads if anything. Our
testing methodology much like it is
in the FX feature is slightly different
from the norm. We tested using a
two-way Crossfire system, which
would allow high end CPUs to flex
their muscles or in a more practical
sense show their worth. It is very
easy to reach GPU saturation in a
single GPU configuration especially
for the overclockers that are only as
brave as water-cooling allows them
to be. The differences in CPUs are
just simply easier to see when there
isn’t a massive bottleneck courtesy
of the graphics card and given
that all X79 boards on the market
support at least three graphics
cards in tandem for now, why not
test with 2 cards anyway.
One thing worthy of noting as well
is that, we tried dual, triple and quad
channel configurations but there
was no difference in performance.
The variance in the numbers was
within the margin of error and we can
only conclude that while synthetic
benchmarks (aren’t they all? -Ed!
) show sizeable gains in available
memory bandwidth with each
populated channel, in practice the
difference just isn’t’ there.
ArmAII, is slightly slower on the
3960X than on the 2600K, however it’s
only 2fps and this is purely because of
the 100MHz frequency deficit of this
CPU. As such, it’s nothing that a small
multiplier bump cannot remedy. Lost
planet 2 however swings the other
way in favour of the 3960X. Resident
Evil 5 however showed the biggest
gains scoring nearly 20fps higher
than the 2600K and over 56fps higher
than AMD’s best showing. A single
and relatively old game is no reason
to buy a CPU, but if ever there were
tangible benefits in gaming from the
purchase of this CPU, this benchmark
has shown them. 3DMark03 seemed
to love this CPU, doubt if it’s thread
related, but most likely related to the
vast quantities of cache or simply
12 The OverClocker Issue 17 | 2011
the 4-way IMC working it’s magic,
whatever it is, this platform will rule
3DMark03 provided you can find a
CPU that can clock sufficiently high.
The rest of the synthetic tests save
for 3DMark05 are benefitting from
the additional threads of the CPU,
delivering scorching performance
all around. 3DMark05 was a peculiar
one, suffering from the lower clock
of the 3960X. Do keep in mind that
while some of the results don’t
show a massive gain over a 2600,
it’s important to realize that this is
only the overall score and not the
individual CPU test scores. The
3960X scores massively here and
benchmarks like 3DMark11 and
3DMark06 for different reasons
undersell that difference. The Vantage
result is probably the most telling of
all the 3D tests as the numbers are
very impressive especially as the
clock speed increases.
Out-Take
We observed something while
working with the 3960X that we
didn’t expect or at least had
not experienced with the LGA
1155 CPUs. It turns out that if
you disable cores, you actually
decrease the total available L3
cache. An obvious assertion
one would make right. Well, not
exactly. See on the 2500/2600/2700
CPUs, disabling the cores and
even leaving two functional doesn’t
necessarily rob you of performance in
largely single threaded benchmarks
like 3DMark05 for example. However,
we disabled all but two cores on the
3960X for heat purposes but found
that the 3DMark03 scores dropped
dramatically, in fact in the region of
5,000 points for 3DMark03. CPU-Z
reported the same cache amount as
before at 15MB, but when reading the
literature provided by Intel it turns
out that each core can only ever
have access to 2.5MB of L3 cache
exclusively. So with only two cores
enabled only 5MB of L3 cache was
available in total, less than that on a
2500K even.
We are not equipped with the right
tools yet to do cache latency tests,
scaling and controlled workloads
but suffice to say, this is the only
logical conclusion we can reach
right now. We may be completely of
the mark, but we did not observe
this difference in scores when
disabling half the cores on the