Intel's Pentium 4 E: Prescott Arrives with Luggage
by Anand Lal Shimpi & Derek Wilson on February 1, 2004 3:06 PM EST- Posted in
- CPUs
Half-Time Summary
At this point we’re done with talking about all of the microarchitectural changes that have gone into Prescott. We know it’s a lot of information so let’s go through a brief rundown of what we’ve learned so far:
- Prescott’s 31 stage pipeline by itself makes the processor significantly slower than Northwood on a clock for clock basis.
- Prescott’s L2 cache, albeit larger than Northwoods, has a higher access latency – also resulting in lower performance for the 90nm chip
- Through improvements in branch predicting, scheduling algorithms and integer execution, Intel has managed to hide a lot of the downsides to extending the pipeline.
- The large L2 cache also helps keep the pipeline full.
- SSE3 instructions will be useful down the road, but the impact given today’s software will be negligible.
- Extending the pipeline to 31 stages will allow Prescott to scale to speeds in the 4 – 5GHz range next year. It will take those speeds to make Prescott a true successor to Northwood.
With that said, let’s look at more of the common areas of discussion about the new chip.
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Stlr22 - Sunday, February 1, 2004 - link
post*Stlr22 - Sunday, February 1, 2004 - link
KristopherKubickiEarlier you said that I should read the article.
What was your point? What was it about my first pot that you disagreed with?
KristopherKubicki - Sunday, February 1, 2004 - link
#7:I agree 100% with Anand and Derek. This processor will be a non-event until we get in the 3.6GHz range. Similar to Northwood's launch.
#10:
Check out our price engine. We have already been listing the processor a week!
http://www.anandtech.com/guides/priceguide.htm
http://www.monarchcomputer.com/Merchant2/merchant....
cliffa3 - Sunday, February 1, 2004 - link
In the table on page 14 it shows that the 90nm P4@2.8 will have a 533 MHz FSB, but is that the case? I did some quick google research and can't find anything to support that...please confirm or correct, thanks.NFactor - Sunday, February 1, 2004 - link
Yes, I must agree this is an amazing article, one of the best i have ever read. Thanks.Xentropy - Sunday, February 1, 2004 - link
VERY interesting article. Thank you Anand and Derek! One of the best I've read on Anandtech, and I consider yours the best hardware site on the net!One correction, on page 7, you say, "if you want to multiply a number in binary by 2 you can simply shift the bits of the number to the right by 1 bit," but don't you mean shift to the left one bit (and place a zero at the end)? It's much like multiplying a decimal number by ten for obvious reasons.
Anyway, it looks like the Prescott is somewhat of a non-event at this time. Just new cores that perform fundamentally the same as the current ones at current speeds. The real news will come later; Intel has just positioned itself for one hell of a speed ramp to come. Northwood was clearly at the end of the line. One analogy, I suppose, would be that Intel didn't fire any shots in the CPU war today, but they loaded their guns in preparation to fire.
The coming year will be an exciting one for us hardware geeks. I'm interested in seeing how higher clocked Prescotts play out as well as whether anything 64-bit shows up before 2005 to support AMD's stance that we need it NOW.
Again, thanks for a very thorough article!
Stlr22 - Sunday, February 1, 2004 - link
KristopherKubickiSo what's your take on these new Prescotts?
KristopherKubicki - Sunday, February 1, 2004 - link
Anand scolded me for not reading the article :( I only read the conclusion and the graphs. Turns out the decision making isnt as clearcut as it sounds.As for the thing with the inquirer. Well, lots of people had prescotts. We had one back in August I believe. The thing is they were horribly slow - 533FSB 2.8GHz. Everyone drew the conclusion that these were purposely slowed processors that were jsut for engineering purposes. While the inq benched this processor, most people didnt just becuase they were under the impression this was not to be the final production model. Hope that clears up some discrepancy about the validity.
Cheers,
Kristopher
wicktron - Sunday, February 1, 2004 - link
Hehe, I guess the Inq was right about this one. Where are all the Inq bashers and their claim of "fake" benchies? Haha, I laugh.Stlr22 - Sunday, February 1, 2004 - link
KristopherKubicki - "read the article..."lol that might be a good idea, as I only broswed it and read the conclusion. :D