32-bit vs 64-bit

I'm wondering what opinion people have of running SL on 32-bit machines versus 64-bit ones. On first flush, it seems obvious that, all other things being equal, a 64-bit machine would be better. But not all other things are equal.

For example, chances are pretty good that I could get a solid 32-bit machine with 2 or 4 CPU cores for about the same as one with a single 64-bit CPU core. Given the same clock speed, I'd bet that two 32-bit cores would run SL faster than one 64-bit core, since SL is multithreaded.

Then there's clock speed. For the same price, you're going to get a much higher clock speed out of a 32-bit machine than you will a 64-bit one. There must be some threshold of difference in clock speed where the two machines would display about the same performance with SL, but I don't know how to quantify it.

Perhaps there are other factors I'm not considering. I'm eager to hear what people who have played with both have to say.

- Lavanya

since when?

if your poll is only for SL, then there is no use using a 64bit chip since its a 32bit program.

Most hybrid 32/64bit chips, like AMD64, intels EM64T, and even IBMs PPC 970 have different modes. They can run a pure 32bit mode, where you can run a 32bit OS, and all 32bit applications. They have 2 64 bit modes, one a full 64 bitmode that requires a 64bit OS and all 64bit software, and a compaitibily 64bit mode that requires a 64bit OS, but can run both 64bit and 32bit software (though not quite as well as full 64bit mode). If you running a standard install of Windows XP on your 64bit chip, then you arent even running 64 bit.


Also, clock speed... aka GHz... aka Frequency, is not a speed rating of the processor. its a speed rating of how fast things are moving inside the processor yes, but many chips are more efficient than others. a more efficient chip can get the same job done by actually doing less things, even if its a lower frequency. Like the Intel Core Duo is a very efficient chip. A Core Duo 2GHz chip can actually outperform a Pentium-D 3.2GHz in just about everything, even with 1.2GHz less frequency. The Netburst Core (intel uses in Pentium 4, most current Xeons, and the pentium-D and some Celerons) is a EXTREMELY inefficent design, it has to be clocks up to a very high clock speed just to keep up with other chips. Intel is releasing all new designed chips by the end of the year, where youll start seeing much lower clock speeds, but faster overall chips.

amd at least typically runs their 64bit processors slower than the equivalent 32bit processor and at the moment SL is a 32 bit app only. This means that right now a 64bit processor won't do you a bit of good unless it's also much faster than the 32 you had or are comparing it to. But, in theory a 64bit processor is an investment in the future. Things, including SL, will eventually have 64bit versions which should run faster than their 32bit counterparts. This could be anywhere from 1 to 3 years down the road. Are you going to upgrade again in that time? if so it might be worth it to wait on that 64bit processor. Compare prices though, if the 64bit processor isn't significantly more expensive, then might as well get it.

First off, dual cores rock the world when it comes to SL and photoshop AND messengers AND poser 6 all at the same time. And the duals from AMD are getting to be cheaper than the single-cores as they phase out the singles.

Second, you WILL get a performance increase in a 64 bit system.

It has nothing to do with it being a 64 bit system by the way. Edit(I didn't explain this comment)L is 32bit, and so is the version of Windows you're probably using.

And SL is single threaded (for now) so dual cores will help only a little as SL will use 100% of a single core CPU and 56% of each core (thus, equivalent to 112% on a single) on your typical X2 processor.

With AMD, the big difference involves the memory controller, which is part of the processor on Athlon64s where it isn't on a 32 bit system (part of the motherboard). Not only does HTT (a trait new to the Athlon series with the 64's) increase speed a bit, but the controller is also much more stable and allows for rediculous performance (and overclocks) without memory instability.

That's something ANY program will use, including SL. And you see it. The difference between an Athlon64 and an AthlonXP/Sempron is night-and-day in SL.

I sell both for Lindens by the way.

If you have a choice, go A64. The cost is usually the same anyway, if not a little cheaper (if you know where to look. Like right here. The guy typing this? great place to look).

Edit: Sally's post on Intel chipsets is quite accurate. They're getting their butts stomped on price/performance by AMD and lost the home desktop retail market majority to them last October, so they're adopting more of their design concepts. If you're an Intel fanboy, don't get the Core Duo, because the motherboards it uses...well, they either aren't made to use them and are hybrids, or they just flat suck. The X2 and Opterons are much better, as I'm sure Torley would agree.

I've noticed that processors receive a performance boost if you're the one selling them.

I stand by my statement that an amd 64 is an investment in the future and not exactly a blow me away performance increase immediately. However the onboard memory controller and price arguments do push the argument over the top to buying an amd 64 now. That's my recommendation for the record .

Has anyone tried to run SL in Windows XP Pro x64 Edition? Any issues? How about with nVidia drivers?

I'm upgrading to a 64-bit system. I have access to the OEM version of XP x64 and wouldn't mind giving it a try, but if it doesn't run SL properly it'll be a deal-killer.

TIA

no, thats not a true statement. I think what you meant to say is you will get a performance increase from an AMD 64bit system.

Remeber that intel too has dual 32/64 bit systems, and they do not have the advantages that AMDs does, at the moment.

much of Intel sucking so bad on the desktop will change in about 6 months.

From personal experience thus far, I agree with what Corvus said.

I am extremely happy with my 64-bit, dual-core Opteron 170. I have multitasking needs to run SL and many other programs at once. While SL itself doesn't take advantage of multithreading in the present, I can still put the extra core to good use.

right on i love my machine .. so happy with it

Gateway® GT5032 Media Center Desktop

Specifications
Processor
AMD Athlon™ 64 X2 4200+ dual core processor
64-bit processor with AMD64 technology
2 x 512KB L2 cache | operates at 2.20GHz | 2000MHz system bus
Operating System
Microsoft® Windows® XP Media Center Edition 20051
Chipset
NVIDIA® nForce® 410
Memory
1024MB DDR (2 x 512MB), 400Mhz, dual channel
Expandable to 4GB
Video
NVIDIA® GeForce® 6100 GPU

Performance is tricky, and there's no guarantee that a 64 bit Second Life if released would be any faster than the 32 bit version would be. The AMD64 extensions can speed up certain types of code in a few situations, but you also double pointer size which increases memory usage and so perhaps leads to more swapping.

Basically, I'd go for the fastest 32 bit chip you can buy ..... who knows when SL will go multi-threaded. I'm not holding my breath, that'd be a major piece of work that nobody is really screaming for yet

Ok, my turn to chime in:

For Annie: You could try it but could be somewhat disappointed. I hear great things about the OS but... if you have any peripherals (scanners, printers, card readers, etc) that dont have 64-bit drivers, then you're out of luck. From the dozens of techncians I talk to, they've all said "it's nice but Vista will offer the same thing but without the hassles". Not sure if SL would run any smoother since it IS a 32-bit App.

The rest:
Q: Why bother with a 64-bit Processor?
A: Um, been keeping up lately? The game industry is hitting a boom with 64-bit updates to their software.

I had the game FarCry running on my old Athlon 3200+. Couldnt turn the graphics up all the way. Even turned down, it lagged WORSE than SL does in busy areas!!! Then I got the 64-bit system. OOoOOOOOooooo!!! I needed tissues!! For tears in my eyes & my pants!!!

Dual Core chips are Sweet! I got mine too soon so it's only single core. Now, from a gaming perspective, a lot of games still dont know enough to take advantage of both cores. In fact it's been known to confuse the crap out of them. You sometimes even have to tell the OS to ignore one of the cores when playing some games. I guess what's happening is, the game tries to use both, gets mixed up and then Crash To Desktop.

As far as AMD vs Intel. Price isnt much of a factor now. Performance is. Intel uses, from what I understand, a different method of implementing the 64-bit code (or did) and this was causing some slow downs. Currently AMD is reigning champ. That may change as was said. But then- Go to AMD's website & look at what they have planned in Processors in the next 3-4 years. Ooooh it is nice!!! How's Quad-Core sound?

Also, when it comes to heat, AMD is winning there too. Intel's chips make nice lil' room heaters!!

I'm also noticing the 32-bit CPU's are slooooowly disappearing from online stores too. It's all going 64-bit before too long, so you might as well build/buy for the future. Windows Vista will supposedly support 64-bit Dual Core CPU's, but I'm not too crazy yet about Vista. I'll wait a year or so & see what happens with it before I consider buying it.

Dual Core CPUs (or Dual CPUs) are more important then 64Bit CPUs.

The points everyone is making are about how an Athlon 4 X2 or a Pentium D run multiple programs better etc. Which is true, none of it addresses the difference that a 64Bit Intstruction set would make.

The big questin for SL would be would 64 Bit intstructions make a diffrenece? Do they do any calcuations that can not be held in a single 32Bit register? If not then a move to 64Bit would not change their proram much at all. The other area that it might improve is that the chips (AMD or Intel) running in 64Bit mode have more registers avialbe to use, but if they optmizied SL for SSE then they are probaly already using the 128Bit registers there and wouldn't need the extra 64Bit ones.

So it really comes back to more being an issue of more CPU Cores = Better. Especially if they SMP SL which would be very nice

Um, all the dual core processors ARE 64-bit. Unless you mean having a motherboard that supports 2 seperate processors.

But I have to agree with the rest of it... I dont think SL takes advantage of newer technologies- Wish it did!!! But then if it did there'd be even more people whining their Pentium 3 w/ GeForce 2 MX couldnt run it

I have a 64-bit dualcore G5. With 64-bit support, I can use more than 4 GB of RAM, which really comes in handy with HD video editing and HDR imaging.

Thanks all.

I understand that SL doesn't yet take advantage of 64-bit features. What I really want to know is whether there is any real problem with running SL under XP Pro x64.

not true. All AMD dual cores are 64bit capable chips. Only some of intels are.

The answer is yes, I have posted a few comments towards a XP pro X64 user who had issues with SL. Why do you or would you want to run XP pro X64, unless its for that 1 program that takes advatnage I dont see a reason to use it because it has to emulate 32bit programs thus making it SLOWER overall.

Thanks.

I actually do have some reasons for wanting to run x64, but they have nothing to do with my SL habit.

What're the timings on the RAM? 2-2-2-5?

And yea, most newer computers can use more than 4 Gig.

I ended up buying a 64-bit AMD system and I regret it. I would have been much better spending that money on a dual-core 32-bit system.

I have no doubt that people who say that 64-bit is better than 32-bit are basically right, but there's a very basic context for comparison: cost. 64 bit just costs more, for now. So if you go 32 bit, you can get more out of it, whether its higher processor speed, multiple cores, or more money for other stuff like video or main memory.

Given how rapidly technology changes, I would not expect the first generation 64-bit processor I bought to be relevant to the "64 bit world of tomorrow", where it will actually matter. Don't buy for the future, unless the future for you is within the next 6 months. 32 bit is cheaper for now, and your 32 bit apps are not going away any time soon.

What 32-bit system is cheaper?

If you're talking about a desktop system, you'd be hard-pressed to actually buy a 32-bit one. And almost certainly not a dual-core 32-bit system; the only dual-core 32-bit CPU is the Intel Core Duo (not the new Core Duo 2, which is fully 64-bit capable), which is mostly found in laptops. Notable exceptions: the new iMac and Mac Mini.

If you're talking about a laptop, you might have a point. Until very recently, the Turion 64 (single-core) was the only 64-bit laptop processor available, and a Core Duo will outperform it. The Turion 64x2 is now available, and it is competitive with the Core Duo in performance (though, alas, not battery life), and 64-bit. Then in a month or two, we'll start to see Core Duo 2 laptops, which should be faster still -- and 64-bit capable.

Principle 1: Try it, and measure the results.

Principle 2: In general (that is, answer not necessarily tailored to Intel or AMD), a 32-bit app will run faster than a 64-bit version of the same app <bold>on the same hardware<\bold>. The main driver for a 64-bit app is when the app needs to directly address *huge* amounts of memory, where huge is greater than about 4GB.

Consider this: if all your longs and pointers change from 32-bit to 64-bit, the cpu has to move twice as much data, and the data takes up twice as much cache and register space.

Principle 3: 64-bit machines are usually newer than 32-bit machines, and are faster for that reason (newness). On older machines, the circuitry gets clogged with crud which slows them down.

SL needs more than just a CPU.

I got a nice chrismass present. A 3Ghz P4 with 800Mhz FSB, Dual bank ram, Sata-300 hard drive and guess what?

I ran out of money and can't afford a video card and my old AGP card won't fit into the new PCIe 16 slot. Or maybe I'm just too cheep

SL will run, but it's slow when running on the "Intel extreme graphics"

I am still running SL on my older system.