Nebie Question

eoinmurphy

I'm starting a Computer Science Degree in Ucd this year and am looking for a laptop.

I was just wondering if this would be sutible.
I am concerned whether the 64bit Turion will cause me hassle programming for normal 32 bit computers.

Just wondering...
Any help would be greatly appreciated.
Cheers,
eoin

Syth

For your information, UCD's computer science department uses Java a lot. In first year you only learn java.

MrPinK

eoinmurphy wrote:

I am concerned whether the 64bit Turion will cause me hassle programming for normal 32 bit computers.

Unless you get the 64-bit version of windows, the code you produce with the laptop will be identical to code produced on a 32-bit machine. Even if you do use 64-bit windows, it shouldn't really cause you hassle if you're coding well. You'll just have to recompile code (or not, depending on the programming language) if you want it run on a 32-bit machine.

eoinmurphy

So i should be grandgeting the lappie.
Grand job. Thanks for all the help, eoin

Inspector Gadget

MrPinK wrote:

Unless you get the 64-bit version of windows, the code you produce with the laptop will be identical to code produced on a 32-bit machine. Even if you do use 64-bit windows, it shouldn't really cause you hassle if you're coding well. You'll just have to recompile code (or not, depending on the programming language) if you want it run on a 32-bit machine.

I would have thought that you'd only generate 64-bit code if:

1. Your compiler supports a suitable 64-bit compile target (AMD64/EM64T/whatever)
2. You ask it to generate code for such a target
3. You're compiling a language directly to machine code.

Java, for example, runs on a virtual machine, so the foibles and intricacies of the actual hardware it's running on is up to the JVM and the host OS to sort out, not the programmer or the compiler.

In practice, having a 64-bit x86 processor is no different to having a 32-bit x86 processor, except that if you have an OS and applications that are compiled to take advantage of the 64-bit extensions, they may perform a bit better - however, by how much does depend a lot on the applications in question.

Hope this helps,
Gadget

rsynnott

Since they're doing a CS degree, they may be using the operating system choice of communists

If you run a 64-bit UNIX-y thing (typically Linux, FreeBSD or Solaris), with gcc, then you will indeed have to go to some extra lengths to produce 32bit code. This is not in itself a big deal.

AMD64bitness makes big speed difference for databases and a few other specialised applications, mild speed increase for most applications under recent 64 bit Linuxes and UNIXs, mild performance hit/no effect/very mild increase for WinXP64bit and early AMD64 Linuxes. Except in areas where there are specific advantages, compilers make most of the difference.

theexis

rsynnott wrote:

mild performance hit/no effect/very mild increase for WinXP64bit

I presume you're referring to 32 bit apps running on 64 bit Windows (WOW64) in relation to a performance "hit"? Its reasonable that the ability to access > 1TB RAM within a process space is meaningless to most home users, but having double the number of CPU registers on x64 is beneficial to most applications natively compiled for 64 bit since more work is done without going out to L1/L2 cache.

rsynnott

theexis wrote:

I presume you're referring to 32 bit apps running on 64 bit Windows (WOW64) in relation to a performance "hit"? Its reasonable that the ability to access > 1TB RAM within a process space is meaningless to most home users, but having double the number of CPU registers on x64 is beneficial to most applications natively compiled for 64 bit since more work is done without going out to L1/L2 cache.

You also need a decent compiler to get a performance increase (very early AMD64 versions of GCC tended not to use the extra registers, for instance).