First of all, does your $750, or $1000 price limit need to include a monitor?
Let me run down the most important things to look for. One thing I
always try to do is get twice the manufacturers recommended specs
RAM: 512 or more, like Jonathan says. Autodesk says at least 256. RAM
is also relatively cheap, so definitely get the 512.
CPU: Unlike Jonathan, I think as long as you get a P4, Athlon 64,
Athlon XP, or Pentium M, you will be just fine. CPU prices go up very
quickly as they get faster and newer, so you can save a lot of money
by looking one generation back (like with the Athlon XP). Just stay
away from Celeron, Duron, or Sempron chips from Intel and AMD, and
CPUs from other manufacturers for Autocad. Autodesk only recommends a
Pentium III 800 MHz, so any modern chip will be at least one
generation newer and twice as fast. This is where you'll save the
money to make your budget.
Video card: ATI or NVIDIA, although for Autocad which uses OpenGL, I
would lean towards NVIDIA. Don't get any other manufacturers. You
don't have the money for an ATI FireGL or Nvidia Quadro video card,
which have drivers made specifically for autocad and would really make
a difference. Autodesk doesn't have a recommended video card, but they
do have a list of features the card should have:
http://usa.autodesk.com/adsk/servlet...linkID=2475323
Luckily, any card made by ATI or NVIDIA in the past 2 or 3 years has
all those features. An ATI 9200 or later or Geforce 5200 or later
should be just fine.
Monitor: Every place I've done any CAD work has always had a 19" or
greater CRT, or a 18" or greater LCD. A large LCD would definitely put
it out of your price range, so look at the 19" CRTs. I've seen new
ones for less then $200 and refurbished ones for less then $100.
Hopefully you already have a monitor, or else you probably won't get
it for less then $750.
I don't think the Poweredge 400SC is the best deal, because although
it starts cheap, you still have to add an OS, video card, etc.
disclaimer: I've never used Autocad for windows, so my
suggestions are based on reading hardware reviews and autodesk's site.
Ask ChrisH if he is happy with the computer I helped him spec out for
Autocad a few years back