Well sometimes it's nice to have a box that has no sentimental value, no collectors value and something you aren't proud of that just has to be perfect. I keep trying to build my perfect box which means I easily end up with nothing to play on while it's being worked on, cleaned, waiting for parts, etc., etc.

Problem solved!

Take one of my Dell 4600's from a previous project. check.
It has already been cleaned. check.
Power supply already disassembled, cleaned, inspected and tested. check.

Remove RAM and install a single DDR 400, 256MB stick. check.
Leave whatever CPU is in it. check. (ended up being a Northwood 3.2)

Already has a 250GB Seagate IDE drive in it, DVD-ROM drive and floppy drive.
Slap one of my Quadro 380 XGL's in it. (Plenty of power for the task at hand)
Toss in a Turtle Beach Santa Cruz sound card for its front panel audio for the Dell case (I play Thief with headphones only), Sensaura 3D audio and good sound quality.

Load up Windows 98 SE, DirectX 7.0, drivers and Daemon tools.

Install Thief 1 and 2 (various others too) and rejoice with no jerking or lag. I know the AMD K6-3+ is really trying hard not to lag but she just doesn't have the horsepower for some of the 1998-2000 era games. She will still be treated with respect and finished for earlier stuff including DOS.

Never take this computer apart again and play the crap out of it, kick it around and play some more and resist the temptation to install a Quadro FX 3000. It just doesn't need it... or XP.