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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INTC - Monday, February 2, 2004 - link
Ummmm yea, kinda reminds me of cooking an egg on an Athlon XP http://www.biggaybear.co.uk/Menu/Aegg/Aeggs.htmlcliffa3 - Monday, February 2, 2004 - link
something good to include on the mb compatibility article would be what boards would house the 2.8/533...i'm wondering myself if the E7205 chipset would...i have a p4g8x, and it would be a welcome upgrade with HT and all the other goodies if it oc's well.Stlr22 - Monday, February 2, 2004 - link
They didn't burn down, but the proc were running hot. Not to mention, these are the FIRST releases in the Prescott line. What's it gonna be like later on?....Just think, a P4 based computer that turns your living room into your very own Sauna!!....WHOOO-HOOO!!.....now that's what I call a bargain!
INTC - Monday, February 2, 2004 - link
The message is clear: Anandtech and all of the other review sites didn't burn down so I guess it's not a flame thrower.Prescott is not as fast as I had hoped but is definitely not the step backwards as some were rumoring it to be. I think a Prescott 2.8 @ 250 MHz FSB will be really nice to play with until I see what Intel announces at IDF in a few weeks.
Icewind - Monday, February 2, 2004 - link
The message is clear: Im buying an Athlon 64.Vanners - Sunday, February 1, 2004 - link
Did anyone catch the error in Pipelining: 101?if you halve the time for a stage in the pipeline and double the number of stages. Yes this means you can run at 2GHz instead of 1GHz but the reality is you're still taking 5ns to complete the pipe.
Look at it like a motorbike: You drop down a gear and rev harder; you make more noise but you are still doing the same speed.
The only reasons to drop down a gear are to break through your gears (i.e. slow down) or to rev significantly higher than the change in gear ratio in order to move faster (with more torque).
The trouble Intel has is that they drop down a gear then rev 6 months to a year later.
kamper - Sunday, February 1, 2004 - link
Just curious, Anand or Derek: what board did you use to get the 3.72 GHz oc? Obviously it wasn't the intel board used in the benches. I guess we'll hear all about this in the compatibility review though :)keep up the good work, that last point about smaller margins at higher clockspeeds (vs. Northwood) was cool. Let's just hope the pattern continues.
Stlr22 - Sunday, February 1, 2004 - link
Seems to me like people either got cought up in some of the hype and expected to much or some people expected to little and that history would repeat itself (Willamette vs Palomino)The fact that the Prescott fared much better in it's launch compared to the Willamette might be a hint to not underestimate it. Prescott isn't really looking bad now, and I think it will hit stride faster then the Willamette core did.
The next couple of years are gonna be really interesting.
Damn, ya just gotta love it!
ntrights - Sunday, February 1, 2004 - link
Great review!KF - Sunday, February 1, 2004 - link
I've grown to appreciate CRAMITPAL. If you read around the opinionated diatribes, he has some good stuff that people avoid saying for fear of retaliation. I suppose if I were in love with Intel, he would tick me off.But, it does look like Intel has created a CPU that should ramp up to speeds high enough to beat the A64 in 32bit mode, and that is all they needed to do.
Regardless of how much heat that is going to take, Intel must have some way in the works to handle it.
Looks like they might not charge an arm and leg for it, which is the biggest shock.