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rich novak
12-19-2003, 03:37 AM
hey all. quick question.

which is more important, a faster frontside bus or a faster processor? for example, let's say there's a p4 3.2 with 533fsb, vs. a p4 with a slower processor but an 800 mgtz fsb (i'm just throwing these numbers out for the sake of asking...). which one is more important? i'm thinking the processor speed, but why?

thanks!

ren

GregHess
12-19-2003, 12:22 PM
Ren,

First off...you can't compare numbers anymore. They just don't give a decent guage of performance.

Numbers pretty much got thrown out the window a few years ago. Their only purpose now, is to differentiate different processors in the same line.

Just take a look at Athlons and P4's...64 and 32 bit. You'll give yourself a nice headache figuring out which one is best for your application...unless you have alot of money, then just get the fastest AMD out and laugh at Intel :).

But its not just different processor companies....Look at Intel themselves.

Just look at the Centrino CPU's...running 600 megahertz slower then a P4 Mobile, and giving it a nice backhand :).

Here's a quick example to your previous FSB question.

Lets take two intel processors.

A 2.8C and a 2.8B. The C runs at 800 FSB, the B at 533.

Is the C faster? Hell ya, but its not necessarily due to to FSB.

Its also because its got hyperthreading, which the B (533 chip) lacks.

If I was going Intel, I wouldn't get anything less then a 800 FSB chip with HT.

MattClary
12-19-2003, 01:10 PM
Amen. I run a P4 3 ghz with HT, but the only reason I'm not using an AMD chip is that I use LightWave, which utilizes the SSE2 extensions when rendering. If I were building a machine today, I would probably give the new 64bit AMD chips a go, as they use SSE2 also (the 32bit Athlons don't).

Thalaxis
12-19-2003, 03:20 PM
Processor clock speed vs fsb (or in the case of the K8 family, the
system memory bus speed -- the fsb is internal to the processor)
is a bit of a balancing act.

And at the risk of sounding repetitive, any comparison will fall
flat on its face unless you're comparing the same architecture.

The reason that the Xeon family has big caches is to make up for
the fact that they have slower FSB's, even in the "c" iteration.
The extra cache hides the fact that the memory is slower from the
processor.

AMD's integrated NorthBridge accomplishes the same thing, but is
a more extreme approach, and as such also makes for a lot of
inconsistency when you compare numbers with P4 platform
numbers.

allawy
12-20-2003, 02:01 AM
rich

My last upgrade was from a FSB533 to FSB800 same speed, well, it's a long story why I did this :), anyway, I can say that the system worthed the extra money I paid for, the FSB800 with the HT just boosted the System performance about 10-20%, now by this I mean Windows XP, all the background proccess, Disk proccesses, startup and so are faster, I'm not sure how fast but noticablly faster that I won't go back, I stoped my Dual Xeon purchase because of the FSB speed.

Now, I'm not a hardware wiz. but I saw allot of systems, and worked with allot. If I'm not wrong the FSB800 with proper DDR Ram can duoble the ram bandwidth, and this will for sure has some serious performcane gain.

for me if I to buy a 3GHz FSB533 or 2.6 FSB800 I would choose the 2ed, this is my openion :)

Keep in mind that Render power is mainly a GHz thing.

Dreamabyss
12-20-2003, 03:21 AM
Originally posted by MattClary
Amen. I run a P4 3 ghz with HT, but the only reason I'm not using an AMD chip is that I use LightWave, which utilizes the SSE2 extensions when rendering. If I were building a machine today, I would probably give the new 64bit AMD chips a go, as they use SSE2 also (the 32bit Athlons don't).

I see that the Athlon 64 FX is in the same price bracket as P4 2.8 so that makes for a compeling reason to go AMD. Except...doesn't the 64 require newer type of rdram that is more expensive? What other things need to be considered $$ when going with the 64 option? Is it possible to put together an Athlon 64 system in the same price bracket as the P4 and which one is going to perform the best?

I would love to see some benches of these two processors using Lightwave. I'm wondering whether Hyperthreading on the P4 is going to give an advantage over the 64 when it comes to render?

Novakog
12-20-2003, 05:33 AM
Originally posted by Dreamabyss
I see that the Athlon 64 FX is in the same price bracket as P4 2.8 so that makes for a compeling reason to go AMD. Except...doesn't the 64 require newer type of rdram that is more expensive? What other things need to be considered $$ when going with the 64 option? Is it possible to put together an Athlon 64 system in the same price bracket as the P4 and which one is going to perform the best?

I would love to see some benches of these two processors using Lightwave. I'm wondering whether Hyperthreading on the P4 is going to give an advantage over the 64 when it comes to render?

The Athlon 64 FX runs at about $750 and the P4 2.8 runs at $250... The 64 FX (not the regular 64) requires registered RAM (is it SDRAM? Can't remember...) that is more expensive. In Q1 2004 the 64 FX is going to 939 pin (from 940) as well as using non-registered RAM. The other Athlon 64s do run non-registered ram and they are about the same price range as P4s that are a little slower, the Athlon 64 3000 is as cheap as P4 2.8 and a little faster, though not much. The Athlon 64 FX is as fast as a P4EE 3.2 and is $200 cheaper.

I can't find the site but I believe the P4EE is faster in multi-threaded renders (the test I saw was CineBench), by how much I can't remember. The P4EE is slower in everything else though.

Thalaxis
12-20-2003, 06:19 AM
Originally posted by Dreamabyss
I see that the Athlon 64 FX is in the same price bracket as P4 2.8 so that makes for a compeling reason to go AMD.


For a lot of applications yes. Well, sort of... the Athlon64 is quite
compelling, but if you're looking at an Athlon64FX, you should
consider a pair of slower Opteron 2xx's instead. It's probably a
better buy, even though the Athlon64FX is a great product. It will
almost certainly come down in price eventually, but until then it's
probably just going to be one of those premium products that
people look at, wish they could justify spending the money on,
and end up buying either its little brother or its daddy instead.


Except...doesn't the 64 require newer type of rdram that is more expensive? What other things need to be considered $$ when going with the 64 option? Is it possible to put together an Athlon 64 system in the same price bracket as the P4 and which one is going to perform the best?


Rambust? From the company that championed DDR when even
Intel insisted that Rambutt was the memory of the future? :)

Novakog already answered that though, so I won't repeat his
answer here.

Which will perform the best? Well... the short answer is "yes".

The long and more useful answer is going to depend on a number
of factors, like the primary use of the machine, and whether or not
you need assloads of memory.


I would love to see some benches of these two processors using Lightwave. I'm wondering whether Hyperthreading on the P4 is going to give an advantage over the 64 when it comes to render?

Yes. In CineBench it's nearly a dead heat in single-threaded
performance, and HT gives the P4 around a 20% boost.

But that's not a universal gain. Cinema is just highly optimized for
HT, as well as for SSE2. Whether or not there is any performance
being left on the table for the Opteron will probably remain an
open question until Windows XP64 hits the streets.

The same applies though with a smaller gain from HT in LightWave
and Max, though Max6 is an unknown at this point.

Edit: format error.

Dreamabyss
12-20-2003, 06:44 AM
Originally posted by Novakog
The Athlon 64 FX runs at about $750 and the P4 2.8 runs at $250... The 64 FX (not the regular 64) requires registered RAM (is it SDRAM? Can't remember...) that is more expensive.

Oops...I meant the regular 64. The FX is way beyond my budget. I was interested in knowing the differences between the P4 2.8 800mhz and the plain ol' Athlon 64. I assumed the P4 with Hyper threading would be faster than the 64...least until applications take advantage of the processor.

rich novak
12-20-2003, 07:41 AM
what i'm looking for really is a fairly powerful machine that i can use for a while. i've been on this computer for about 3 years now, and it's holding up really well! but it's a p4mobile 1.6, with 8 megs (!!) video ram. if i had a nice workstation right now, i'd be learning a lot more and producing some real output.

i'm seeing a lot of dual athlon systems out there. i run lightwave. if p4 is better for lightwave because of the ht issue, i'd still like to have a dual processor system, but i can't find a dual p4 system out there. i see a lot of dual p4 motherboards, but i'm no computer builder. any advice here?

my little laptop is great for typing college papers on, but for lightwave... i feel like i'm abusing it a "little bit."

thanks for all the info folks!

ren

Thalaxis
12-20-2003, 03:33 PM
For duals, you need a Xeon (it's pretty much the same processor,
though).

The AMD equivalent is Opteron; it's pretty much the same thing as
an Athlon64FX, but the 200 series are configured to work in dual
configurations.

Even though the P4's give better rendering performance than the
Athlon64's, the reverse is true in OpenGL rendering (i.e. the
viewports).

rich novak
12-20-2003, 04:32 PM
good info!!

Novakog
12-20-2003, 08:02 PM
Originally posted by Thalaxis
Cinema is just highly optimized for HT, as well as for SSE2.


But the Athlon 64 FX (not the regular A64s) has SSE2 as well also, correct?

Even though the P4's give better rendering performance than the
Athlon64's, the reverse is true in OpenGL rendering (i.e. the
viewports).

Wait, isn't OGL rendering purely graphics card? You must mean the other aspects of the "so-called" rendering, such as dynamics calculations, and all the "operations" that you do in the workflow (such as poly smooth or really anything you do), but the rendering itself is purely GPU.

Thalaxis
12-20-2003, 09:52 PM
Originally posted by Novakog
But the Athlon 64 FX (not the regular A64s) has SSE2 as well also, correct?


All of the K8's support SSE2. I don't think they'll really strut their
stuff without code that's tuned for them though, since I suspect
that the K8's strutting its stuff will require using the extra SSE
registers.


Wait, isn't OGL rendering purely graphics card? You must mean the other aspects of the "so-called" rendering, such as dynamics calculations, and all the "operations" that you do in the workflow (such as poly smooth or really anything you do), but the rendering itself is purely GPU.

The graphics card gates performance, but there are other
bottlenecks also. Also, with most modern graphics cards, the
drivers eat quite a few processor cycles anyway.

The main reason that the K8 has such impressive display
performance (it's been pretty consistent in both gaming and
proessional software) is that the K8 connects to the AGP port via
one of the HyperTransport links on the integrated NorthBridge.
That means that the connection to the AGP port has both high
bandwidth, and low latency.

In other words, the K8 is better at feeding the GPU, and needs
less time to order it around :)

glitterboy
12-20-2003, 11:10 PM
Originally posted by Dreamabyss
I see that the Athlon 64 FX is in the same price bracket as P4 2.8 so that makes for a compeling reason to go AMD. Except...doesn't the 64 require newer type of rdram that is more expensive? What other things need to be considered $$ when going with the 64 option? Is it possible to put together an Athlon 64 system in the same price bracket as the P4 and which one is going to perform the best?

I would love to see some benches of these two processors using Lightwave. I'm wondering whether Hyperthreading on the P4 is going to give an advantage over the 64 when it comes to render?

the fx51 is nearly 1100CDN vs 2.8c 310CDN. i love to see where you found the fx51 that cheap?

Thalaxis
12-21-2003, 12:20 AM
Originally posted by glitterboy
the fx51 is nearly 1100CDN vs 2.8c 310CDN. i love to see where you found the fx51 that cheap?

I think it was a minor miscommunication -- it should have been an
Athlon64 3000+, which is around $250; the 3200+ model is
around $400 or so.

Novakog
12-21-2003, 01:07 AM
Originally posted by Thalaxis
The main reason that the K8 has such impressive display
performance (it's been pretty consistent in both gaming and
proessional software) is that the K8 connects to the AGP port via
one of the HyperTransport links on the integrated NorthBridge.
That means that the connection to the AGP port has both high
bandwidth, and low latency.

In other words, the K8 is better at feeding the GPU, and needs
less time to order it around :)

Oh ya, good point. I always thought that the reason faster CPUs had faster frame rates in games was because of stuff like AI and dynamics calculations, but I guess it's both a factor of both that and the connection between the processor and AGP port...

Hey, do you know whether the nForce3 250 has full HT capability (i.e. 1.6 Ghz transfer rate with 6.4 Gb/s bandwidth, as opposed to 150 - 800 Mhz with a 3.2 Gb/s bandwidth)?

Thalaxis
12-21-2003, 07:47 PM
Originally posted by Novakog
Oh ya, good point. I always thought that the reason faster CPUs had faster frame rates in games was because of stuff like AI and dynamics calculations, but I guess it's both a factor of both that and the connection between the processor and AGP port...


All of that's there too -- and all of them can be quite limited by
data transer limitations.


Hey, do you know whether the nForce3 250 has full HT capability (i.e. 1.6 Ghz transfer rate with 6.4 Gb/s bandwidth, as opposed to 150 - 800 Mhz with a 3.2 Gb/s bandwidth)?

I think so, but I'm not entirely certain.

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