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Pentium IV study
InQuest has published a study of the Pentium IV. It
found that because of the P4's cache design, it uses 4 times the memory
bandwith a PIII does on random access data benchmarks. Even on benchmarks which
benefit from the larger cache-line size, the P4 shows no benefit due to its
higher clock rate. Furthermore, the 1.5GHz P4's thermal diode throttles the
part to effectively 750Mhz as soon as power consumption exceeds 54.7W. Without
this limitation, a P4's maximum consumption would be 72.9 watts, similar to a
1.33 GHz Athlon's 73 watts.
Not nearly as much as far as I can tell. Then again it doesn't need as much.
To run IA64 code you need a IA64 OS. To run 64 bit AMD code you need a minor change to the context switching code (you need to save 64 bits of data per GPR, and twice as many GPRs). Of corse you need more OS support for a 64 bit address space.
To produce good code for the IA64 you need some extremely advanced compiler technology. Unrolling loops isn't enough, you have to modulo schedule them. Good AMD64 code is hardly different from normal x86 code.
Now there are IA64 OSes, and at least a compiler or two. Intel did get something for their hype machine efforts, and for having some machines around for people to test on. I don't think the AMD 64 bit stuff is as far along, but it won't take long to catch up.
Besides a lot of the IA64 mind share is folks calling it the "iTanic", AMD may not want that kind of mind share :-)
I don't think anything in the IA64 is as useful as SMT (as seen in the next gen Alpha, and rumored to be in the next IBM Power CPU). Pretty much everything in the IA64 has been seen before BTW. I do admit it is more innovative then the 64 bit AMD CPU though, but not all innovations are worth the price of buy in...
Of corse two years ago I felt differently about the IA64 (and I have a stack of IA64 docs to show for it), and in two years I may change my mind again...
Intel to cut up to 60 per cent off P4 prices
I see even classic Slashdot is now pretty much unusable on dial up anymore.
Why would you say Intel is likely to dominate the platform?
Fact: AMD now holds twenty- to thirty-percent marketshare.
Fact: AMD Duron and Athlon processors are now spec'd by all but one mainstream, brand name supplier.
Fact: The latest AMD processors outperform -- and are widely reported as such -- the latest Intel processors.
Fact: AMD K6-2 mobile processors have a 20% marketshare, and AMD K7-family processors are gaining marketshare.
Fact: Intel keeps fucking things up. And I mean *seriously* fucking up. From backing Rambus to failing chipsets to bolloxing up its relationship with their customers... oh, gahd, the list is endless.
So, how do you foresee Intel dominating the platform war? What I foresee is a an ungainly beast of a has-been chip design and manufacturing company, shooting itself in the foot and chopping its own legs off, while an upstart executes cleanly and quickly, soon to overtake it...
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Don't like it? Respond with words, not karma.
By an amazing coincidence, I was just reading this article when this story came up on /.
If tits were wings it'd be flying around.
I still think it is still too early to pass any judgements on the Pentium 4 CPU.
The reason is simple: we are repeating history in terms of Intel CPU architecture development.
I think many of you remember the Pentium Pro CPU, which came out in 1995. While it was very fast for its day in terms of 32-bit applications, it was a bit poor for 16-bit applications. Yet, the P6 CPU core that the Pentium Pro pioneered became the basis after numerous refinements for the Pentium II/III and Celeron CPU's, which run very quickly with both 16-bit and 32-bit applications and was not matched until the AMD Athlon came out in 1999.
As it stands, the Pentium 4 CPU core design--which is brand new in many aspects--has only begun its development curve. I expect dramatic improvements in performance as this new core design is improved over the next few years.
Raymond in Mountain View, CA
Correct. And the real money corporate customers buy Intel primarily because
1) Intel has better OEM vendors lined up for their market (Dell/Compaq/IBM). This channel is the key. AMD primarily gets what's left (home/soho/BYOB).
2) Intel has a much better reputation. Little things like that "What chipset bugs?" scene when the K7 was launched don't help. The key here is that if Intel tries to force RAMBUST or buggy shit like the i820 down Mr. MIS's throat they are dead in the water, so they are dancing on pinheads.
3) The corporate market could give a shit which processor can do 10fps better in Quake or if some CPU is slightly suboptimal at running legacy code (which after all was designed to run much slower computers to begin with). They are simply looking for a price/performance/supportability sweet spot that they can standardize on.
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Business. Numbers. Money. People. Computer World.
- they pointed out the fact that P4 performance is no greater than lower-clocked Athlon. This is true. However, with Northwood P4 should be scaling to 2G and above where it will eventually beat Athlon. (Of course, AMD is not sitting still, but P4 is supposed to have more headroom than Athlon due to its superlong pipes.)
- They criticize the power throttling; this would be a moot issue after the processor is shrunk, at least for the lower end P4s.
- They point out that nobody wants to buy the current P4 due to its dead-end packaging. This is also true, but presumably the new socket for Northwood will be around for a while. (I have no idea why Intel thought to introduce the 850 while admitting that it would be dropped in less than a year, but that's what they did.)
They even acknowledge the price drop. AMD competed for years with inferior processors priced low. Intel can certainly compete with Northwood.Anyone care to comment on this seeming discrepancy?
Assuming that it really is thermal throttling, I would love to see what a good tech site like Tom's might be able to determine about the throttled down CPU when using various heatsinks. If that feature is really there then you should expect more powerful heatsinks give the same temperature as lesser heatsinks, but higher performance.
In other words, it is possible to see this as a feature, not a bug. You get 1.5G when the processor is capable of it. You get half that when you are running hot; but with good enough cooling you should always get the highest performance possible.
"Overclocking" may go away, replaced by "overcooling".
Otherwise, why would the sub $400 USD computers be so popular? Show a consumer a 1.2 GHz AMD based computer and a 1.5 GHz computer, at a even $200 price difference and expect to see the AMD win.
It's all well and good that the Pentium IV has some design "issues", and I think many of us here at /. expected this. Unfortunately, much of the purchasing decisions in the real world are based on sheer numbers: Dollars, Gigahertz, or both.
Look at the success of Microsoft Dos and Windows. There were certainly better alternatives out at the time for everything DOS and Windows did (PC-DOS, DR-DOS, even Macs). Microsoft primarily won the OS and Apps market because of its hugely successful marketting push. The only thing the average person heard in conjunction with "Computers" became "Microsoft".
Or consider America Online. There were many ISPs before them (remember netcom?), but the veritable hailstorm of "Free" floppies and CDs bought AOL the lion's share of Internet Service Provision.
The fact is that unless the Pentium has a serious flaw in it (fdiv, F00F), it will do reasonably well just because it has "1.5ghz". And as we all know, that more gigahertz must mean better technology!
In future news... Watch as Intel attaches a Ring Oscillator to their P5 chip running at 10ghz, unused by the rest of the chip.
-Ted
Intel... lure the mainstream... just plain bad... lost market share and customer respect... unwise... poor... many new alternatives... not...thrilled.
Intel...predicted...fastest... shipments...below expectations... bad omen.
The market...will not pay a premium... Intel is hoping... frustration.
Intel...criticizing AMD...Athlon. P3...well supported.
But now...instability of the P4 platform...P4 lacks...market...confidence.
P4...will undergo...five major changes...
Users...aware...weaknesses... Intel's...problem is the platform... band-aid.
Brookdale...difficult...DDR...competition.
Intel...frustrated...cripple... wide open for all...competitors.
P4 needs...strategy... DDR... escapes...Intel's marketing folks... familiar territory.
Intel...deny...problem... vigorous defense of Rambus.
elaborate thermal and power regulation requirements... toaster oven.
Intel... publicizing... amazement... only 54.7 Watts... below the fastest Athlon.
Pentium 4... unbalanced... weakest.
Intel's... elevated costs... horrific... price slashing.
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Dude, he said scientific computing, which is memory intensive by definition. The P4 cleans up this because its memory system is so much faster than P3/Athlon. He's not playing video games, he's doing real computation.
Oh, btw, redo your benchmark taking price/performance into account...
For starters: he said the P4 slaughtered the UltraSparc III. Have you priced one of THOSE recently? Hint: they're much more expensive (and rare!) than P4 systems.
Second: One of the departments in my company bought a bunch of $40,000 HP workstations. They also bought one $1,500 P4 system. They did benchmarks and found for THEIR APPLICATION, the $1,500 P4 was 3.5 times faster than the $40,000 HP. I'll leave the price/performance for this one as an exercise for the reader.
Third: For price/performance on SPECfp, the P4 does VERY well. It is about 10% slower than an 833MHz Alpha, and about 1/5th the price (it is faster - and cheaper - than all other speed grades of Alpha). Additionally, it is cheaper and faster than any other RISC machine.
Fourth: people who need the highest performance (i.e. P4 level memory and FP performance) usually pay a huge premium. In this sense, the P4 is a bargain (especially after the price cuts).
4 in roman numerals is IV. When the average consumer realizes he spent triple the money on something worth half as much, the paramedics may need to give him one of those. Cooincidence?
I am !amused.
You have to take anything that Bert McComas says regarding Intel with a grain of salt. He is probably one of their biggest critics and I've never heard him say anything positive about their technology.
I'll give you an example: He says that the chip will slow down when you try to extract useful performance from it. He bases this on his misunderstanding of the THERMTRIP circuitry. Yes, it is true that the P4 will dissapate more energy when you make it run a heavier load. Yes, it is true that if the die on the chip gets too hot, the chip will slow down to protect itself. But that completely ignores the fact that it is up to the system vendor to insure that the chip never gets too hot. Right now, I'm looking at a P4 system that I was a designer on. Not only do we have a fansink on the P4 itself, the chassis has four separate fans to dissapate heat, and one of them is a monster 5-incher. There is no way that one of our systems is going to overheat the P4 and cause it to slow down.
Unfortunately, customers don't seem to appreciate thermal management in their buying decisions. But keep in mind that all 1.5GHz P4 systems are not alike.
That the Pentium IV is a marketing ploy by Intel to keep AMD from grabbing all the market share with their superior products.
Didn't we already know that?
The only plus side from my viewpoint is I was going to buy some 500 MHz Pentium II chips, which should drop in price.
What about the power consumption claims from Intel on the Pentium IV - anyone got any specs on that?
--- Will in Seattle - What are you doing to fight the War?
Note they say: "Perhaps Intel was a little frustrated that its own 815+PC133 platform beat RDRAM last year. This time Intel will not screw up - they will doubly cripple SDRAM to make certain that it cannot match RDRAM. In other words, Intel seems willing to publicly impale Northwood on an entirely inadequate Brookdale platform in order to make its point. It is this type of agenda that causes further doubt about Intel's commitment to the P4 platform and leaves the door wide open for all of Intel's competitors."
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And note the CPU rampup - yeah, it will run faster than a P3, so long as you don't ask it to run fast for very long. Kind of like a car that goes 0-60 mph in 0.1 seconds, but if you actually try to get to top speed of 125 mph, it will suddenly kick in the limiter and drop you back down to 115 mph. Sure, the car's rated to do 250 mph, but it can't actually run at 250 mph.
Translation - very sucky. Trying to fight AMD on "bandwidth" by faking it and also fight Transmeta on low-power by using a heat limiter (faking it). It saves power when demand gets high by cutting throughput, instead of Transmeta which saves power when demand is low, but lets you use full power when you need it.
"Scotty, I need more power!" "Sorry, Cap'n, but the speed limiter just kicked in - I can give you warp 1.3, or if you turn off the shields and the phasers, I can give you our full rating of warp 9. Of course, then we'll die anyway
Yup, sounds like Intel
--- Will in Seattle - What are you doing to fight the War?
Once I finish this reply, I will return to the air-cooled T-bird on my dining room table that is being happy as happy can be running at 1.6 GHz. This is with a $140 mobo, a $220 chip, and a $10 fan in a good case. After I get an OS on it, I will run Tim's benchmark. Dare say if past is prologue, it will surpass the 2.2 GHz P4 when that turkey is released.
Sorry to say, but Intel has let the marketing types run their company a bit too long. The blue man group is probably going to be the folks that are blue because their investment in Intel stinks so maybe their use in their advertising is more than appropriate.
Sex is heriditary, if your parents didn't have it chances are good you won't either.
If I had to pick one reason why Intel is likely to sell lots of inferior P4s at higher prices than AMD's superior chips, I would have to say: GHz. P4s simply run at higher clock speeds than AMD's and Joe Consumer doesn't know that AMD chips are faster per Hz than Intel's. He'll simply buy the one with the bigger number. And the clueless sales people at consumer electronics stores don't help much either. I'm sure the following conversation is happening in stores across the country right now:
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Clerk: Can I help you?
Joe: Yeah, I'm looking for a computer.
Clerk: Oh, what you want is the new spiffy Intel Pentium IV that has 1.5 GHz!!!
Joe: What's a GHz?
Clerk: It's, uhhh, a thing that tells you how good your computer is. Having 1.5 is really, really good!!!
Joe: Oh, OK. What about that one over there? [points to a less expensive AMD-powered computer]
Clerk: Oh, well, that one only has 1.2 GHz. It's not a bad computer, but I'll tell you, personally, I'd never buy it. 1.2 GHz aren't nearly enough for today's demanding applications such as web browsing and e-mail!!!
_________________________________
As much as I hate to admit it, Intel made a good decision when they increased the depth of that pipeline: They decreased the speed, but they increased the only thing that matters to computer buyers, the GHz number. What AMD really needs to do is start an advertising blitz showing how much faster their chips are at a lower clock speed (and a lower price). Otherwise, Joe Consumer (and those clueless clerks) will never hear about it.
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
The Pentium IV is essentially still in development. And considering that it debuted at 1.5Ghz, I don't think this should be any surprise.
We already knew that the P4 offered less performance, clock-for-clock, than other modern chipsets, but it is nice that someone has identified why. Also, it's about time that more people realize just how important cache performance can be.
However, the real question here is, what can we do about it? I mean, switching to AMD is fine in the short term, but Intel is likely to dominate the platform war in the long-term. And the P4 will likely be the first step in migrating people to their new architectures. Unless AMD's Sledgehammer is wildly successful, they will have an enormously more complicated cloning job on their hands.