My second desktop computer running Linux, and (currently, 2001-09-29) the Linux desktop of mine longest in use, is my IBM Aptiva E3N. When I purchased this system, it was state of the art. Granted, now it's quite a bit behind the times, however, it is a very resilient system with equipment that Linux supports 100%.

• 300Mhz AMD K6-2 w/ 100Mhz FSB
• 64Mb SDRAM - 256Mb Max (allows some mixing)
• 6Gb HDD
• 32x CD-ROM
• 512Kb L2 Cache
• ATI RagePro Turbo AGP w/ 2Mb VRAM (onboard)
• Crystal Audio CSC8025 (onboard)
• 3 empty slots- 2 PCI, 1 ISA
• 1 empty half-bay (ZIP drive size), NO EMPTY FULL BAYS (grumble, grumble, gripe)
• 2 USB slots (ALi M5237 controller)
• Lucent SoftModem (PCI card, removable)

• Crystal Audio CSC8025: Supported by the 'cs4232' driver with the 'opl3' MIDI driver, this onboard audio device has been supported since early 2.2.x kernels (possibly supported in the 2.0.x kernels as well). Support seems to be perfect (I haven't noticed any troubles in several years now). The only issue (and this can be more of a distro problem) is that you may need a program such as setmixer to ensure your volume settings are restored after reboots. This isn't the best card, but it seems to have good Linux support.
  • Crystal Audio CSC8025 - CSC0101 Game Port: This game port was supported under the 2.2 kernels, but with 2.4 that support was accidentally lost. Here is fixed source for the 'ns588' kernel module in the 2.4 series. It has been tested on kernels up to (and including) 2.4.9. It should make it into the kernel source soon. In order to use the game port on the IBM Aptiva E3N under Linux, you will need this fixed module.
• ATI RagePro Turbo AGP: As you probably already know, onboard video or audio usually sucks. The onboard Crystal Audio is mediocre (though well supported under Linux), and the onboard ATI RagePro is mediocre as well. However, it does have some very nice XFree86 support. The 4.1 XFree86 release saw some preliminary hardware acceleration support for this card using the 'ati' driver. Traditionally, the card has used the 'mach32' driver The card is also fully supported by the Linux framebuffer. Also, in-spite of what Win32 reports your max. resolution/bpp on this chipset is, you can get 1152x864x16 on it. Yes that's right, you get better res. under Linux on this card ;-)
• Lucent SoftModem: The Lucent SoftModem (WinModem) was (of course) not always supported. However, you can get some very functional drivers for it here or from the LinModems.org website. SoftModems still suck, and 56kbps is far too slow and crunky, so I actually yanked this thing out long before the appropriate drivers were made for it ;-)

• Free Slots: You only have 3 free slots, 2 PCI and 1 ISA, making installing new cards a pain. Currently, I have a 3Dfx Voodoo 2 (PCI) and a 'ne2k' ethernet card (PCI) occupying the slots. The ISA slot is placed such that it is very difficult to have both it and another PCI slot filled at the same time. There are only two SDRAM slots, and one comes filled with the 64Mb chip. You can combine RAM of different sizes and speeds (which is very nice), but if you want to max out your RAM, you will need two 128Mb SDRAMs. Plus, I have many many many problems with them supplying us with a AGP port, but hardwiring the crappy ATI into it on the motherboard!
• Empty Bays: That 6Gb HDD sure didn't last long before it was full, so I had to add a 2nd HDD (30Gb) within a couple of years after I purchased it. The problem was that the 6Gb was a full-sized drive, taking up the free 5 1/4" bay! And there were no other free bays for a new drive. Ultimately, I kludged something together to make it work (I forget the specifics, but it involved building a new bay :-/ )
• Mid-Tower Case, with cramped interior: The case is supposed to be Mid-Tower, but the layout inside is kind of stupid and doesn't give you a whole lot of room. Some PCI cards actually will not fit inside the case. Plus, adding new bays (like I had to do for the 2nd HDD) are very difficult because they tend to hang very close to the motherboard. And don't even get me started on how little room you have for cabling!