buying a new computer...

[jdratlif]

I need help deciding on what kind of computer to buy.

Should I buy a 64-bit processor? What are the benefits? I only seem to hear negative things about them, e.g. program xyz doesn't have a 64-bit version and so it doesn't run. Would I need special versions of all my programs? I want my new machine to last, but it needs to work today also.

What about cores? Should I just buy a dual-core, or are there compelling reasons to consider a tri-core or quad-core? I do not play games, but I do compile and use video conversion software. Will I see more benefits with more cores? mencoder for mpeg2 doesn't seem capable of using multiple cores, but I can encode two videos simultaneously. I'm pretty sure gcc/g++ is multi-core aware, so I should see a benefit when compiling large projects, right?

Speaking of processors, what's the deal there? Is a Pentium D the same thing as a Pentium Dual Core? Is that the same as Core 2 Duo?

What about virtualization? Will VirtualBox or Xen or whatever work better with processor ...?

Since I don't use games, the video/audio selections seem moot. I'll use whatever they have integrated. But there may be better choices for linux. Are there particular video/audio choices I should look for to get the best linux support?

[Panzer88]

most programs don't need a 64 bit version to run on a 64 bit system, they just don't take ADVANTAGE of the 64bit system unless they have a 64 bit version.

[Nach]

Should I buy a 64-bit processor?

Most definitely.

What are the benefits?

Certain types of operations which typically are ones that deal with large numbers run MUCH quicker with a 64 bit CPU.

Proper SHA 512 hashing for example using a 64 bit CPU runs in about 1/4 of the time of a similar 32 bit CPU.

RSA Encryption with very large keys runs like in like 1/20 of the time than if 32 bit.

Complex SQL queries run in like a half or a third the time.

There's all kinds of other operations where you'll notice major speed up from 64 bit, however this all depends on what you use your computer for.

I only seem to hear negative things about them, e.g. program xyz doesn't have a 64-bit version and so it doesn't run.

Many programs do lack 32 bit versions, but generally that means blame the vendor, not the processor.
However there's methods to get 32 bit programs working without issues.

Would I need special versions of all my programs? I want my new machine to last, but it needs to work today also.

Do you consider 32 bit versions special?
For any application that doesn't exist in 64 bit that you want to use, you'll have to get the 32 bit version.

To get the 32 bit version of an app, you need to also have the 32 bit libraries it needs.
For a most basic app, this generally means no work at all, and it just runs out of the box.
More complex apps it means you have to install all the libraries you would normally need to install, except you need to grab 32 bit versions instead of 64 bit. In some cases you'll already have a 64 bit version of that lib for other apps, so you'll have two versions of the lib installed.

However, personally, I find 32 bit only apps that I use are few and far between. I think I only have 4 or 5 on my computer.

Also in some cases, don't forget that just getting the Windows version and running it in WINE is the simplest method. It's generally not a big deal nowadays.

What about cores? Should I just buy a dual-core, or are there compelling reasons to consider a tri-core or quad-core? I do not play games, but I do compile and use video conversion software. Will I see more benefits with more cores?

The main thing about cores isn't whether or not your app supports multiple cores, but how much multitasking do you do? If you want to run a dozen heavy applications at once on a regular basis, you'll obviously want as many cores as you can get today.

mencoder for mpeg2 doesn't seem capable of using multiple cores, but I can encode two videos simultaneously.

Mencoder for x264 encoding, and probably other codecs as well can take full advantage of multiple cores. I've ripped and encoded DVDs with multiple passes in under an hour with my multi core CPU and MEncoder.

I'm pretty sure gcc/g++ is multi-core aware, so I should see a benefit when compiling large projects, right?

Not in the slightest.
However you can tell "make" how many threads to launch, so it'll compile multiple files at once via multiple GCC instances, if there are no awaiting dependency issues.

Speaking of processors, what's the deal there? Is a Pentium D the same thing as a Pentium Dual Core? Is that the same as Core 2 Duo?

No. And stay the heck away from the Pentium D. The Pentium D is two 64 bit P4s glued together. The chip is slow like you can't imagine. It is the worst 64 bit x86 dual core chip available.

What about virtualization? Will VirtualBox or Xen or whatever work better with processor ...?

Yes, as the 64 bit CPUs today come with visualization extensions. You generally have to turn it on in the BIOS on your motherboard though, for some reason which I haven't yet figured out, they all seem to ship with it off by default.

Since I don't use games, the video/audio selections seem moot. I'll use whatever they have integrated. But there may be better choices for linux. Are there particular video/audio choices I should look for to get the best linux support?

Well there's the whole drivers issue. When it comes on drivers on Linux, it seems nVidia is the only way to go. I keep hearing ATI is finally catching up, but every new ATI video card I see, I can't seem to get it working right at all, while nVidia works right on the first try every time.

[odditude]

all current intel/amd processors are 64-bit capable with the sole exception of the intel Atom series.

pentium d, as nach stated, is two pentium 4 dies side-by-side on a single chip. it's been obsolete for almost 3 years now (replaced by the original core 2 duos)

a pentium dual-core is a core 2 duo with a smaller cache and a slower fsb (read: memory interface)

from what you've said, you'd likely be best off with a c2q 9xx0 chip (unless you're on a tight budget, then grab a q6600 or phenom x4).

if you're loaded, blow a wad on a core i7 and the associated platform.

no matter what you go with, you'll want to grab a chip with hardware virtualization support. this means you definitely want to avoid anything outside the c2d 8x00, c2q 6x00 or 9xx0, core i7, and phenom series of processors. the c2d 7xx0, c2q 8xx0, pentium, celeron, athlon, and sempron chips largely have hardware virtualization support missing or disabled.

i can't help you on linux support, but as long as drivers are available for alternatives, i would avoid intel integrated graphics like the plague.

[Gil_Hamilton]

Pentium Dual-Core is basically the Celeron of the Core family.

Pentium D, again, is a dual-P4. BAD! Unless you need a heater.
...
I'm actually surprised that you can still FIND Pentium Ds.




If you're building cheap, it's worth noting that the bottom-end Pentium Dual-Cores are ABSURDLY overclockable. As in you can get 80% boosts without any effort whatsoever.

I'm running an E2140(stock speed 1.6 GHz) overclocked to 2.8 GHz.
It gets a tad warm under load, but nothing uncomfortable.
Sure, I only have half the cache of a Core2 Duo, so it's not a total performance gain, but... it was a lot cheaper, and I was building on a budget.

[Nach]

the c2d 7xx0, c2q 8xx0, pentium, celeron, athlon, and sempron chips largely have hardware virtualization support missing or disabled.

Not so. I own a 7500, and it has virtualization support.

Code: Select all

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[snkcube]

I'm actually surprised that you can still FIND Pentium Ds.

Some laptop vendors still use them for their low-budget selections.

[Gil_Hamilton]

I'm actually surprised that you can still FIND Pentium Ds.

Some laptop vendors still use them for their low-budget selections.

*horrified*

[Panzer88]

on a side note, my dad was looking into upgrading with something cheap, I was wondering what would be a good motherboard to go with this

http://www.newegg.com/Product/Product.a ... 6819115017

I'm new to the whole "build your own" PC but it looked pretty good.

[Demios]

Unless you actually plan on running a 64 bit OS don't stress it. Most decent procs go both ways anyway. It all depends on if you are running a 32 or 64. While we are on the subject, The average person does not need a 64 bit OS. Yet anyway.

[odditude]

Not so. I own a 7500, and it has virtualization support

I stand corrected. Good thing I followed my own advice and looked at Intel's spec finder before making blanket generalizations, huh?

Pentium Dual-Core is basically the Celeron of the Core family.

...and then there's the actual Celeron Dual-Core, which is an even further stripped down model.

[Nach]

Unless you actually plan on running a 64 bit OS don't stress it. Most decent procs go both ways anyway. It all depends on if you are running a 32 or 64. While we are on the subject, The average person does not need a 64 bit OS. Yet anyway.

Well, not much point in specifically buying a 64 bit CPU because you want the advantage of 64 bit applications, and then installing a 32 bit OS on it.

Need is also hard to quantify. Technically don't need a computer at all. However if you find the desire for 64 bit apps, then you need a 64 bit OS.

[grinvader]

I'm actually surprised that you can still FIND Pentium Ds.

Some laptop vendors still use them for their low-budget selections.

*horrified*

Hey, it's almost winter (in the northern hemisphere, at least) and some people are interested in additional pylo- err, heat sources.

[jdratlif]

Wow, this place is better than slashdot.

Okay, so to recap, 64-bit is the future. I need to get a 64-bit OS or I won't be able to take advantage of any 64-bit applications. My 32-bit applications will work fine, but will need 32-bit libraries. What exactly makes an application 32 or 64-bit, or libraries for that matter?

Without being multi-core aware, I can't take advantage of multiple cores with a single program. If I multitask though, I can. So if I opted for a dual-core, I could encode video and not have my web browser/email app affected. If I had a quad-core, I could encode 3 videos simultaneously while browsing the web.

gcc/g++ is not multi-core aware, but make is. It can use as many cores as I have available to run gcc/g++ if the dependencies allow for it. Compiling will likely be faster.

If I decide to go Intel, I want Core 2 Duo or Core 2 Quad, not Pentium D (assuming they are still around) or Pentium Dual Core. If I go AMD, Phenom X3 or X4 are the best choices.

Linux support for nvidia is best.

Virtualization works better with the new processors. Xen looks like it might be worth a try, and the newest version supports AMD or Intel VMX extentions.

[funkyass]

This short of is this: you can't get a CPU that doesn't support 64-bits, unless you go out of your way

The beauty of the way 64-bits is implemented is that, if you are running a 64-bit OS you can run 32-bit software, you need to have the correct libraries.

All modern OS's are multi-core aware, you gain benefit from such a CPU, even if your specific applications are themselves not designed for such a CPU. using the g++/gcc(well, make to be specific) as en example, you can run more than one instance g++ at the same time. Encoding a video would be faster, as any OS (eg disk access)calls that the encoding calls would be executed on the other CPU.

[creaothceann]

What exactly makes an application 32 or 64-bit, or libraries for that matter?

Well, the file header. The code also consists of new opcodes, and expects the CPU to work differently.

http://en.wikipedia.org/wiki/X86-64

[Nach]

Wow, this place is better than slashdot.

Okay, so to recap, 64-bit is the future. I need to get a 64-bit OS or I won't be able to take advantage of any 64-bit applications. My 32-bit applications will work fine, but will need 32-bit libraries. What exactly makes an application 32 or 64-bit, or libraries for that matter?

Without being multi-core aware, I can't take advantage of multiple cores with a single program. If I multitask though, I can. So if I opted for a dual-core, I could encode video and not have my web browser/email app affected. If I had a quad-core, I could encode 3 videos simultaneously while browsing the web.

gcc/g++ is not multi-core aware, but make is. It can use as many cores as I have available to run gcc/g++ if the dependencies allow for it. Compiling will likely be faster.

If I decide to go Intel, I want Core 2 Duo or Core 2 Quad, not Pentium D (assuming they are still around) or Pentium Dual Core. If I go AMD, Phenom X3 or X4 are the best choices.

Linux support for nvidia is best.

Virtualization works better with the new processors. Xen looks like it might be worth a try, and the newest version supports AMD or Intel VMX extentions.

Yeah, you got all that right.

What exactly makes an application 32 or 64-bit, or libraries for that matter?

Compiling them with a compiler that will output a file which is setup to be 64 bit (header and opcodes as creaothceann the said).

Some compilers have multiple output options. Some compilers only output a particular format, but the compiler itself can be compiled on whichever machine (thus it's a cross compiler).