phuile wrote:
> Yes, I am talking about the "real" quad, not 2 dual core put together.
> I am asking because I was in a discussion on another thread in this
> forum and happened to read that some people are prepared to wait for
> the "real" quad from Intel. The reason being that AMD will have them
> coming "soon" and Intel shouldn't be far off if they want to compete. I
> am just consdering whether I should wait or just go ahead with the
> currently quad Xeon. That's why I am wondering whether anybody knows
> about the time frame.
Well, the answer seems to have been updated recently: not till sometime
in 2008, _after_ Intel has converted to 45nm!
http://www.tgdaily.com/2007/01/27/in...enryn_details/
For Intel with a shared L2 cache, it may not be as easy to redesign it
to accommodate 4 cores rather than just 2. AMD will only have a shared
L3 cache, which is not as performance critical as an L2 cache, so some
design flexibility might be available there.
As for the advantages of a real quad-core vs. dual-dual-cores, we really
won't know the answer to that until AMD launches its real quad-core. So
far people think it won't make a difference, but AMD is claiming that
Barcelona will be upto 40% faster than Cloverton. Pretty much what Intel
claimed Conroe would be over Athlon 64 before it got launched; back then
people were skeptical, but it turned out to be true. AMD might hold
similar aces up its sleeve. We can assume that AMD will implement all of
the same architectural improvements to its cores that Intel did to make
Core 2 so good, so at the very least it will equal Core 2. Then AMD will
have a shared L3 cache between the 4 cores, which should pool common
data among all 4 cores rather than 2; the shared L2 cache worked wonders
for Core 2 over Athlon 64, it was probably worth over 50% of the overall
improvement by itself. Also although Core 2 is a superb computational
engine, it's definitely not state-of-the-art at I/O throughput (i.e.
Hypertransport vs. front-side-bus). It's masking its I/O deficiencies
with big caches at the moment. The I/O throughput equation also includes
communications between processors in a multiprocessor system. When they
scale up over two processors, the FSB is a bottleneck.
Yousuf Khan
--
There is no failure, only delayed success