A few questions about the Athlon 64

[Caveman]

I've been waiting a long time for this chip and have 3 questions. Using the recent performance benchmarks as the "standard":

1.) How much could it benefit by a 64 bit OS? Would this help 32 bit software running within the OS as well as 64. How much?

2.) For the relatively low clock speeds, it seems to blow everything else away. How far could it theoretically scale and what PR rating might it hit by this spring (May)? Would something like 4400 be reasonable to expect?

3.) How can the Barton be faster on many of the benchmarks that were shown?

 

[MDE]

1) Could be a lot, could be a little, depends on the software. 64 bit OS won't change 32 bit performance
2) Nobody but AMD knows, and I doubt they even know.
3) Barton is at a higher clock speed (assuming they're using a 3200+) and had more mature drivers and more optimizations (if any) than the A64.

That said, once the socket situation is straightened out, I'll probably end up buying a higher-end Athlon64.

 

[Caveman]

My target would be a 4400 min PR equivalent before I think I'll buy... Hoping that happens by spring. Thanks for the input...

 

[Davegod]

another Q:
When would you expect Athlon 64 boards to become PCI-Express?

the whole pci-express thing is still causing me concern about buying one of these super $$$$$ graphics cards :|

 

[nowayout99]

Don't get your hopes up on a full 1000+ PR jump in only 6-7 months there, caveman. The last I read, Intel and AMD were only planning on hitting around 4GHz/4000+ by the end of next year.

 

[Duvie]

Originally posted by: MonkeyDriveExpress
1) Could be a lot, could be a little, depends on the software. 64 bit OS won't change 32 bit performance
2) Nobody but AMD knows, and I doubt they even know.
3) Barton is at a higher clock speed (assuming they're using a 3200+) and had more mature drivers and more optimizations (if any) than the A64.

That said, once the socket situation is straightened out, I'll probably end up buying a higher-end Athlon64.

Ditto...An early A64 you may phase yourself out fast for a faster processor. I like to upgrade a couple cpus per mobo so even for me I would wait to the socket change on the A64 before I even considered it. I will likely not even jump on a prescott for about 6-9 months as I will just jump into the p4c and DCDDR mobos and may try a 2.4c now and then a 3.0c or 3.2c when the prescotts drive them down....

I hate being early adopters as the mobos are buggy, sockets change, compatability issues not ironed out, and fing expensive. I buy cpus for 200 or less and often can keep them 6 months and sell them for still 100-150 dollars. uy and a64 out of the gate for 500-600 and wait 6 months and the thing will be around 200 dollars I bet. That is a big loss for me. With loses of only 50 dollars or so I can afford to upgrade a lot...

 

[dullard]

I think the first great Athlon 64 will be the Athlon FX. Did you see the previews where people claimed it beat the 3.06 GHz P4 by 40%-50% in many games? That Athlon FX will be released in the beginning of 2004 (probably late Feb/early March is my guess, does anyone have anything better than a guess?). The first Athlon 64 released in a couple weeks will be significantly slower than the Athlon FX.

To answer your questions the best I can:
1) A 64-bit Windows OS will do very little for your 32-bit software. You have two effects that will degrade performance: 64-bit Windows must translate everything into 64-bit and using 64-bit takes up twice as much register space for the twice as many bits. Yes these are very minor, but they will both have a degrading effect. So all things equal, 64-bit Windows will not help. However there are a few things that computers do now that will benefit from 64-bit. IF the programs are recompiled and slightly reprogramed to optimize it (a) for 64-bit and (b) for AMD chips since Intel won't have home 64-bit chips, then you will see a nice boost on those parts of programs. Whether programers do this is another story.
2) Only AMD knows how far it can scale and they aren't saying. Again I'd expect the Athlon FX to be here in early spring and it seems like a ~3800+ PR rating would fit it nicely (this of course is my own number that I think it deserves).
3) The Barton does frequently have a higher clock speed than many of the Opterons in benchmarks we have been shown. The top Barton is at 2.2 GHz. The Opterons go as low as 1.4 GHz. Sure the Opteron/Athlon 64 does more work per clock but it is efficent enough to overcome a 800 MHz deficit from the Barton. The Opteron doesn't get a 57% boost clock for clock over the Barton thus the 1.4 GHz Opteron cannot compete with the 2.2 GHz Barton. Thus anyone would expect the Barton to win against these slow Opterons. The fastest Opteron available so far is still only at 2.0 GHz. So it needs to be at least 10% faster than the equivalent speed Barton to win any benchmark against the Barton. There are some programs where clockspeed matters more than anything and thus again the top Barton will beat the top Opteron.

 

[opranks612]

You're wrong though, because Athlon64 translates the code at the hardware level, so there is not any slowdown when using 32 bit programs. It was Intel's processors that had to do software emulating, not AMD's.

 

[dullard]

Originally posted by: opranks612
You're wrong though, because Athlon64 translates the code at the hardware level, so there is not any slowdown when using 32 bit programs. It was Intel's processors that had to do software emulating, not AMD's.

It isn't a processor issue - it is a Windows issue like I said. There is one extra layer of translation Windows needs. In Unix there isn't that issue.

 

[Aganack1]

what pr rating will be released next week and in the coming months

 

[Cerb]

Originally posted by: Caveman
I've been waiting a long time for this chip and have 3 questions. Using the recent performance benchmarks as the "standard":

1.) How much could it benefit by a 64 bit OS? Would this help 32 bit software running within the OS as well as 64. How much?

Depends on what you're doing.
64-bit OS and 64-bit apps, or 32-bit apps that don't do much with drivers: a little advantage...or, depending, maybe a huge one. The Opteron benches on Linux so far show a nice improvement, but the compiler also has a lot to do with it. I imagine in gaming, it'll make a nice difference, given how prevalent large floats are.

If there isn't a major jump in gaming performance, then the Opterons will be the ones with the good stuff from 64-bit (and the odd way memory is shared). Mainly in that you can have >4GB of RAM per CPU, and no special tricks to access it. However, in future games, this may be a crucial thing as well.

2.) For the relatively low clock speeds, it seems to blow everything else away. How far could it theoretically scale and what PR rating might it hit by this spring (May)? Would something like 4400 be reasonable to expect?

Right now, we know the Opteron samples reviewers have typically hit 2.2GHz just fine. Aside from that nobody knows, maybe not even AMD (remember, even they admitted surprise at how far the Bartons went). 3GHz is probably a good target number, though, for the current ones.
I imagine it'll scale with intel, just to keep Intel on their toes...AMD may have IBM on their side, but only under certain conditions, and Intel has more R&D money to throw around.

3.) How can the Barton be faster on many of the benchmarks that were shown?

Clock speed. The Athlon64 and Opterons seem to do about as much work per clock as Athlons.

In benchmarks largely involving crunching numbers over and over in sequential order, they can predict what they will need accurately and have it sitting there (the 2000+ tends to be about even with a 1.6GHz Opteron in such cases), so they are close to even per clock, and Bartons are faster. When they can't predict that, it takes time to go to memory, and in these cases, the Opteron beats the hell out of anything, a sit can get there faster. This is probably one of several reasons why the Opteron and Athlon64 appear to whoop some real @ss in games.

 

[Caveman]

Can it be for real that we wont see a PR of 4400 for 16 months? Cmon... I would think that this would happen in under 1 year... Isn't it safe to say that as the Athlon 64 scales, it's *true* speed will scale faster than traditional 32 bit machines?

 

[nowayout99]

Dunno, but it's not good to shoot your whole wad at once either. I'm simply relaying their roadmaps, I don't make them.

 

[Cerb]

Originally posted by: Caveman
Can it be for real that we wont see a PR of 4400 for 16 months? Cmon... I would think that this would happen in under 1 year... Isn't it safe to say that as the Athlon 64 scales, it's *true* speed will scale faster than traditional 32 bit machines?

Yes, but not by enough to raise the PR rating by more than say, 100.
It has several bottlenecks removed, aiding it now and for future scaling, and that will help it live out a wonderful life (I hope), but the only real difference is that it should scale a bit closer to a straight line.

 

[JSSheridan]

Originally posted by: Davegod
another Q:
When would you expect Athlon 64 boards to become PCI-Express?

the whole pci-express thing is still causing me concern about buying one of these super $$$$$ graphics cards :|

We'll see AMD boards with PCI Express in the first half of 04 and Intel in fourth quarter 03. These boards will still come with a AGP slot for at least one years, so don't sweat it. Peace.

 

[magomago]

Originally posted by: nowayout99
Don't get your hopes up on a full 1000+ PR jump in only 6-7 months there, caveman. The last I read, Intel and AMD were only planning on hitting around 4GHz/4000+ by the end of next year.

True- but then again no one assumed we were going to hit 1Ghz as soon as we did

:wine:

 

[miniMUNCH]

From what I understand...winXP 64 bit edition for AthlonXP will include 64bit and 32 bit system files and libraries so that it will not need to do any kind of 'translation' in software...running 64 and 32 bit apps simultaneously on an OS is a matter of book keeping (provided the needed 32 bit libraries are available) but is no different than managing only 32 bit app memmory space and system interaction.

 

[Cerb]

Originally posted by: miniMUNCH
From what I understand...winXP 64 bit edition for AthlonXP will include 64bit and 32 bit system files and libraries so that it will not need to do any kind of 'translation' in software...running 64 and 32 bit apps simultaneously on an OS is a matter of book keeping (provided the needed 32 bit libraries are available) but is no different than managing only 32 bit app memmory space and system interaction.

Yes, but it will slow when you need to interact between the 64- and 32-bit parts (WoW64, correct?). However, with many applications, that may be a minor issue, and in some cases using the additional 64-bit features (mainly registers) may increase overall performance enough to negate all of the possible performance hits. So we'll just have to wait and see.