Pentium 4 3.46 Extreme Edition and 925XE: 1066MHz FSB Support is Here
by Anand Lal Shimpi on October 31, 2004 3:00 PM EST- Posted in
- CPUs
Intel's plans for higher Front Side Bus frequencies come as no surprise to those that have been carefully reading for years now. Back in October of 2001 we outlined Intel's FSB targets for the major core releases of the coming years:
"Although not nearly as high, FSB frequencies are also ramping up as clock frequencies do. Intel's Northwood (0.13-micron Pentium 4) core will eventually use a 533MHz FSB, Intel's Prescott core will use a 800MHz FSB, and their Tejas core will use an incredible 1.2GHz FSB upon its release."
Things have obviously changed since we made that statement, primarily that Tejas has since been canceled and Intel introduced an Extreme Edition of the Pentium 4 based on the Gallatin Xeon core. Given the revised plans, what do present day roadmaps say about Intel's FSB targets for the future?
Today Intel is making the move from 800MHz up to the 1066MHz FSB, with the release of the Pentium 4 3.46 Extreme Edition. Priced at $999, the 3.46EE will be followed up by the 3.73EE as the only two chips to support the faster FSB for almost a year. Current Intel roadmaps show absolutely no support for the 1066MHz FSB from any processor other than the two aforementioned Extreme Edition chips until the end of next year, when Prescott-2M chips will finally receive 1066MHz FSB support; there are also plans for dual core 1066MHz FSB chips although they have not been publicly outlined on any roadmap.
It seems as if Intel isn't interested in releasing a new revision of their mainstream chipsets and wants to thus save the move for Prescott to 1066 for their upcoming Lakeport chipset. What that means is that today we are seeing a very limited launch of a new FSB as a feature exclusive to the Extreme Edition CPUs, no doubt a way of adding more value to the very expensive Extreme Edition offering.
The faster FSB is enabled through a revision to the 925X chipset called the 925XE. The 925XE simply adds 1066MHz FSB support, and nothing more, to the feature set of 925X. By enabling 1066MHz FSB support, the 925XE chipset can finally run the FSB and DDR2-533 memory buses synchronously, offering a balanced 8.5GB/s of bandwidth over each bus while operating at multiples of the same base 266MHz frequency. The end result is that the 1066MHz FSB should guarantee lower latency memory accesses for any chip that uses it with DDR2-533. However it seems that Intel paired the faster FSB with the worst possible choice out of their processor line; armed with an on-die 2MB L3 cache, the Pentium 4 Extreme Edition already has the lowest latency memory accesses out of the entire Pentium 4 line, thus softening the impact of the synchronous 1066MHz FSB.
The other thing to keep in mind is that faster FSB frequencies truly become beneficial as higher CPU speeds cause the bus to saturate with data requests and transfers - strike 2 against Intel's choice of introducing the FSB with the Extreme Edition. Prescott continues to be the higher clocked CPU (not to mention the deeper pipelined CPU of the two), thus making it the better candidate of the two for the 1066MHz FSB.
While some have speculated that Prescott isn't yielding well at the 1066MHz FSB, it would seem that the reasons for not moving Prescott to 1066MHz are much more marketing related. The current 915 and 925X chipsets are not selling well at all and the thought of replacing both of those chipsets with new, 1066MHz FSB versions (especially the high quantity mainstream 915 chipset), so that Intel could migrate the entire Prescott line to the 1066MHz FSB wouldn't go over very well with the motherboard manufacturers. From talking with numerous motherboard manufacturers it would seem that Intel is trying to save any major performance improvements for their upcoming Glenwood/Lakeport chipsets, in order to avoid what happened with 925X/915P where there was no performance improvement over the previous generation of chipsets. This may also be why there is no talk of 1066MHz FSB Pentium 4s on Intel's current roadmaps, all conversation about the future 1066MHz FSB parts appears to be happening over telephone and face-to-face meetings only, the former of which we have been privy to upon numerous occasions recently. It could very well be that even Intel is unsure about what their future 1066MHz FSB plans will be at this point.
We shouldn't eliminate the possibility that Prescott may not be yielding well at the faster FSB. Remember that the major limitation to FSB frequency is CPU packaging, the connection and routing of signals from the solder bumps on the silicon core to the pins (or in this case pads) on the chip itself. It could very well be that Prescott's 7-layer design has a correspondingly more complex packaging layout, resulting in some present day hurdles to increasing FSB frequency. That being said, we have heard more reports of people being able to run their Prescott CPUs at the 1066MHz FSB than those that haven't. Take that for what it's worth.
The Pentium 4 3.46EE replaces the 3.40EE as the fastest Extreme Edition CPU from Intel. However with only a 66MHz clock speed advantage, we would expect almost all of any performance increase we see to be caused by the 1066MHz FSB. But how much performance can we expect from a FSB increase on a processor that isn't the best choice for a FSB increase? Given the simplicity of today's launch (just one slightly faster chip with a slightly modified chipset), let's just find out.
63 Comments
View All Comments
GhandiInstinct - Sunday, October 31, 2004 - link
Come on Dell, cheaper, faster..give in to the grown up taste!!!I still can't fathom Dell being the top computer seller worldwide, are soccer moms buying at record highs?
Tides - Sunday, October 31, 2004 - link
i'd say ddr2 does suck when intel gets less performance with it vs an amd 939 with ddr1. what a waste of cash to have the intel branding.jimmy43 - Sunday, October 31, 2004 - link
Most people dont care whats in their computer. Intel is a brand name people trust, but if they can get a computer for less money which can do all they need, then they will. And guess what? Theyl be blown away, and theyl realize AMD slays Intel and theyl laugh at their friends who got an Intel. The reason Intel is able to hold on so well to the market is because of conservative companies like DELL and other such multi-billion dollar partnerships. I say once DELL gives in, its over for Intel. But seriosly they really need to pick it up...Zebo - Sunday, October 31, 2004 - link
Those gaming benchmarks are embarresing.A "budget" athlon 64 3400 with the "old" socket 754 single channel mem controller is putting a whoppin' on Intels top chip.Zebo - Sunday, October 31, 2004 - link
SLIMYou're forgetting DDR2 price which this needs in your so called Intel is "cheaper" comparison. If you want the same price setup you can get a FX-55 and really bring the wood.
AnonymouseUser - Sunday, October 31, 2004 - link
"why didn't anyone try to overclock this thing and see how far it'll go?"They didn't want to melt the motherboard?
knitecrow - Sunday, October 31, 2004 - link
why didn't anyone try to overclock this thing and see how far it'll go?Determinant - Sunday, October 31, 2004 - link
There is a graph missing in the "Business/General Use Performance" page.The graph for "Ahead Software Nero Express 6.0.0.3" is replaced by a duplicate of the preceding graph.
I was surprised to see the big difference when burning CDs/DVDs with different CPUs until I realized that it was the wrong graph.
I'm really interested to see how much of an impact faster CPUs make for burning CDs/DVDs because I didn't think that there would be a difference outside of the benchmark variance but since this was benchmarked it must have been noticable.
Thanks
MMORPGOD - Sunday, October 31, 2004 - link
None of you are aware of the situation Intel has over the world computing market. Yes evryone here on Anand forum is hardcore or enthusiast of computer tech and gaming for PC. But one thing none of you have a grasp on is that Intel has millions of people who do not define themselfs as ever being knowledgable to computing performance or benchmarks. Basicly all of intel is going to be on top no matter what, unless something big happens where the community who purchases these computer systems from the retail stores either sees whats going on beforehand or just wises up and reads about there current technology. Its something thats proven and works, Intel is leading the world in publications of its product more then AMD, thus they have a hand on being on the top. I am a diehard AMD fan, and there isnt to many of us out there who have been since AMD came out, but I can tell you, with all this media coverage on Intel over the past years, its engraved into evry consumers head that the next PC they get they will most likely purchase retail INtel equiped PC. AMD needs to market a little more because average people dont give a damn about benchmarks. Just my opinion about evryone who I see post above who says man Intel is toast or Intel is gone, those are benchmark comments and dont disolve the real world consumers thoughts on a PC with Intel name. How many people go into a Circuit City or Best Buy and see more AMD products then Intel? Intel leads advertisements and in store showcasing, so until someone actually gives the word to the public that AMD is better, Intel will always lead but not in performace. Cant wait for my FX-55Pythias - Sunday, October 31, 2004 - link
I really hope intel can get it back together, or we're gonna be looking at sky high processor pricing again. We need healthy competition.