I recently got my mitts on an Athlon 64 laptop, and want to try to run some custom simulation code I have in native 64-bit mode.

So, I need a 64-bit distribution. I've been using Mandrake 10, and am pretty happy with it ... but I've never tried anything else (been using mdk since 8, so I'm a relative linux newbie), so what do I know?

Mandrake is making it hard to find 64-bit iso's on their site (although google turned up mandrake10-rc1 for amd64.

That said, I've heard that 64-bit linux isn't the most stable thing out there yet, and that 64-bit gcc is particularly bad.

First off, is it worth it to try to get a real amd64 distribution and do my number-munching in 64-bit mode? I'm going to have to do a few tricks (like ndiswrapper) to get wireless and the other things on the laptop working... do those work in 64-bit-land?

Secondly, what distributions can you folks recommend? Gentoo looks decent, but might be a pain to set up... since I only have access to broadband for a few hours a day.

My code uses 3-d visualisations... is there a problem getting Radeon Mobility hardware acceleration drivers for 64-bit?

(I hear the Win XP 64-bit beta completely, utterly, sucks. Plus there's no compiler so you're running 32-bit binaries all the time anyway, no?)

My hp pavilion zv5000 is able to run SuSE 9.2 Professional 64, WinDOS XP Pro 64, WinDOS XP Home 32, and will soon have FedoraC2 64 plus Mandrake 10 64. The 60GB harddrive is appropriately partitioned, and the only hard part was realizing the secret WinDOS limitations, which are:

No WinDOS can be in an extended partition; only primary partitions will do.
The beta XP Pro 64 will boot even if its primary partition is not "active".
The 32-bit XP still boots only if its primary partition is marked "active".

As of now, I can say XP Pro 64 beta behaves more like a pre-alpha. NOBODY provides drivers for it. When booted, there is no sound, no modem, and no nVidia support. Since the screen is 1280x800, everything is stretched on the display. Every application beyond OS and essential utilities are 32-bit only. So, no noticeable speedup occurs other than file access/read/write times. Both M$ products are installed on vfat format, so Linux can read/write to either M$ partition. Virus checking and firewall (NIS2004) will NOT install, though some 32-bit apps do (the Firefox/Thunderbird/OpenOffice trio work, as does my DeLorme mapping). Oh, and expect a crash and burn every 10 minutes or so, unless only one user-space app is running.

As a user of boxed SuSE 9.2 Professional, it was only necessary to take out the 64-bit DVD that came in the package, and boot from DVD. I told it to use the desired extended partition for swap and /, allowed it to install Linux and then download and install all updates, then gave it my local network settings (leary of DHCP, so any such are "untrusted"). I went back to updates with "manually select" rather than "auto select" to get my nVidia 64-bit driver. All was operational, including modem, firewire, etc. It screams, it operates perfectly. I've not done benchmarks with the 32-bit machine, as I'm still busy building this 64-bit testbed.

Fedora C2 Athlon64 iso's are widely available for free download, even as DVD. Mandrake10 64 DVD is not, but I allowed MandrakeClub to con me into Silver membership to download the DVD (tomorrow?).

The SuSE partitioning tools and boot loader are sufficient for all this booting magic, though it did take some trial and crashing. Enjoy!

I have an Atlon64 but dont use x86-64 instruction set at all.
I won't unless Slackware bring one out.
If you're gonna use 64 use SuSE 64 0 bits the best out there at the moment.

<eom>