P4 v Athlon: Number Crunching

[Howard]

I just read Toms comparison of P4 and Athlon systems for office and gaming use. "To cry or Not to Cry" Jan 30.

But I have a single objective: speed of floating point number crunching, say using C++. Do people think that the P4 with PC800 RDRAM is going to be faster than Athlon systems for heavy floating point number crunching?

Howard

 

[wapaaga]

i'm not sure which is better
bu i would say keep the money and get more ram
at school the commputer i work for vc++ 5.0 has a celron 500
with 128 megs of ram

at home i have vc++6.0 with a 450 p3 and 96 megs of ram

and i gusses that each ram speeds it up becuase for some reason my commputer at home complies slower with the newer version of vc++ than the ones at my school

 

[FUGGER]

http://www.spec.org/osg/cpu2000/results/cpu2000.html

P4 wins, and comes in close to Alpha 64bit.

Its gonna be nice when P4 gets die shrink to .13 micron

 

[Grizely1]

No. The FPU on the Athlon is superior to anything of Intel's.

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Satan Clara...... 'Nuff said.

 

[Howard]

Grizely...interesting, and thanks for replying, but is there any evidence for that? How do you reconcile what you said with the FP run time benchmarks at SPEC where the P4 1.4 seems to be a lot quicker, more than twice as fast for 183equake for example?

Howard

 

[Grizely1]

I'm not saying anything about benchmarks or anything, just that Athlon's FP unit is much more advanced and faster than Intel's. Ask anyone, they know. Look around for some articles on it, I'm sure you could find some.

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Satan Clara...... 'Nuff said.

 

[Guest]

Yes, the AMD FPU is vastly better than intel. 20% at same clock. Factor in the price comparison and you've to choose AMD. When ever tom releases benchmarks for cpu's he always includes 3dsmax 2 renderings per hour table. Everyone seems to look past this but that I the only thing I look for. Btw, for FPU duron and tbird have the same scores since cache doesn't factor in at all here. A Duron/tbird running at 700mhz ties a Pentium 3 at 1000mhz. Not bad at all.

 

[Howard]

hi mkelder

THanks,
I cant find toms P4 and AMD benchmarks for 3dsmax...do you know if they're on site?

 

[Guest]

I believe the P4 has worse FPU than the P3. I know it can't touch the duron/tbird for sure.
Here is the P4 FPU benchmarks (you'll laugh hard, intel want to sell processors to people that want to surf the net, not have power)
http://www4.tomshardware.com/cpu/00q4/001120/p4-23.html#floating_point_performance_under_3d_studio_max_2

Here is the duron/tbird vs the P3 1000mhz
http://www4.tomshardware.com/cpu/01q1/010108/duron850-08.html

 

[Howard]

mkelder

Thanks, very interesting ... but now I'm puzzled because the SPEC FP benchmarks at

http://www.spec.org/osg/cpu2000/results/cfp2000.html

show the Intel chip a lot faster than AMD 1.2Gz.
How do we reconcile these different findings?

 

[Guest]

From what I have been reading the P4 seems to perform better in graphic heavy applications. The Athlon Tbird is a well rounded chip that performs well in all areas. If you want a pure gaming chip and dont mind the cost the P4 is nice. For a well priced all around sweet chip the Athlon Tbird simply rocks.

 

[Grizely1]

Only because the P4 has superior bandwidth (tons of it)!

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Satan Clara...... 'Nuff said.

 

[Guest]

Howard,
Take a look at this.
http://www.highend3d.com/tests/maya/testcenter/
It has results for the same file on different processors/machines. Maya uses huge amounts of fpu calculations for 3D rendering.It is also a good test of ram speed because its high ram usage. The single Athalon is the higest single in the group and higher than most of the double P3s. I personaly am waiting for the dual Athalon boards to come out. If the numbers of the dual Athalon 1200 is two times a single, (like the p3s) the dual Athalon will post numbers that have never been seen before.
Anim88tor

 

[Guest]

When are the dual althons coming out anyway? I have P3 500 and it really needs to be upgraded. Was going to get a 850 Tbird and oc to 1ghrz. If they are coming soon I will hold off.

 

[Guest]

Acording to AMD zone the board will be released at the end of QI, next month, and the 760 MP will be released early Q2.
Its anyboby guess as to when we can actualy get our hands on them,from the example of the 1200, maybe June???
Anim88or

 

[Guest]

Hmm, sounds interesting, I think I could wait that long.

 

[Guest]

I have yet to find any Athlon perform better than a P4 with Rambus. Even the Athlon 1.2 with 266 bus and DDR does not outperform in grapic heavy applications. If anyone has a link please put it up I would like to compare.

 

[Guest]

That depends on the use of the cpu. If you want to render in any 3d app AMD has it hands down. That is all I care about really, I could care less if I get a few fps less in quake 3, that loss is made up by the 100's of dollars you'd save going with AMD. With that money you could upgrade other stuff or just have more pocket money.

 

[Grizely1]

That's called bandwidth usage, and we're not talking about that.

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Satan Clara...... 'Nuff said.

 

[cutepunk]

Seems like you don't have a clue, Grizely1, sorry to say.
Athlon's FPU can't be called SUPERIOR to that of Pentium4's. SPEC numbers, which can be called 'the maximum potential of the core," basically shows you what the CPU can do when the software is properly optimized for the CPU. Athlon/Duron are pretty much optimzed for programs that are designed to run best on Intel's P6 cores... after all, they don't have a choice.
On the other hand, P4 takes a different approach to improve the FPU performance. That is, as you probably heard a million times already, SSE2. SSE2 is a double-precision 128bit instruction set, and x87 FPU is not. P4's cache lines are optimized to move data in 128bit chunks, so when P4 is working with old 80bit x87 FPU instructions, it is not efficient. That's why P4 performs rather poorly (but not bad at all..some of the lost performance is due to the data in programs used to benchmark are not properly arranged for P4's 20-stage pipeline) on programs that heavily uses old x87 FPU instructions, like the 3Dmax which Tom likes so much. In some programs like Quake3 though, P4's massive bandwidth kicks in and makes up for some of the inefficiency.

SPEC numbers tell you what P4 can do... smash Athlons and Durons and even some Alphas when it gets the SSE2 support, which I think it will get enough when Northwood is launched.


Sorry for the poor English.. I'm not a native speaker.

 

[AmdMELTDOWN]

dude,no matter how you explain this to the "amd puppies" they will never get it.

when a benchmark tool fails to see and use P4 144 new instruction set then you know that the numbers are bogus.

they should all label their tests scores "handicap P4 results"

amd puppies are just as blind as some of these benchmark tools!

 

[Lucol]

Exactly, the problem is most people don't really comprehend how the SPEC benchmarks work. If you've ever worked with Borland C++ or similar that has the Intel optimized compiler(bcc32i) as well as the regular compiler(bcc32), you can see huge performance differences even on the same processor. It's simple, Intel makes very good compilers for their processors, where as AMD does not seem to shine in this area. If AMD would put some more resources into making compilers that optimize for their processors, it's possible that they could gain some serious ground in the SPEC benchmarks. For home use, or regular office use, I'd go with an AMD any day, but for in house development, I'll go with Intel, the performance differences are usually pretty staggering.

 

[jeffg007]

You made some good points. Yes p4 will be faster with sse2 software but how many programs are there at this point, not very many.

Don't for get that AMD has rights to use sse2 and it will be in there next chip. Right now the P4 is a bad choice 1 because very few program use SSE 2 price of a p4 sucks.

Jeff

 

[tfbww]

So, are you saying the SPEC has been SSE2 optimized? I honestly have very little clue about SPEC. Is it really an apples to apples comparison when what the person wanted to know was raw FPU performance? It *seemed* like he was using compiling as an example, not really the heart of the question. Just asking.

 

[Sojourn]

The Athlon's FPU can and is rightly called superior to the P4's. The PIII's FPU is stronger than the P4's. SSE2 can make up for it, and even make it perform better in some cases, but most software isn't optimized for this yet. If you are talking about CPU performance on todays software, the Athlon is hands down the superior performer, unless you are buying your machine specifically to DivX encode movies and play Q3A, and in the case of Q3A the additional cost of the CPU and memory do not make up for the extra performance since the increases are imperceptable to the human senses. Once more software filters down the pipe I would consider purchasing a P4, but right now it just doesn't make sense. For the money you'd spend on a 1.5GHz P4/RDRAM system today, you could buy a T-Bird/PC133 SDRAM system and swap out the motherboard/CPU/memory 6 months down the road when software can cope with the P4 and Intel/Rambus offerings become competatively priced. You'd have a screaming system now, and a screaming system then, and come out better than if you'd bought just the P4 system today. The biggest thing to consider with the P4 is what you plan on doing with it. It beats the Athlon in some real world benchmarks (optimal condition benchmarks like SPEC do not relate directly to real world performance!) quite convincingly, but unless you plan on using it for that specific purpose (Q3A and MFlask) I would recommend the Athlon. It performs solidly across the board so you don't have to worry about buying a program and having it run slower than an 800 Celeron you just replace on that spanky new P4 1.5GHz becuase its developers didn't know how to optimize for SSE2, or more likely just didn't care to. You also don't have to sell your daughter's virginity to buy it and its memory. If you look at the P4 performance in today's real world benchmarks, and stack that up against its price, and the price of the memory you are required to use with it, there really doesn't seem to be a lot of thought required.

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