"Blind Joni" wrote in message

I need to upgrade an existing machine.

It is an ABIT MOBO running a Celeron 1.3 with old PC100 ram.

1. Can I replace the MOBO and Processor with a new one running a P4,
probably a 3.0 or so..it needs to be an Intel processor.

The old motherboard should be an ATX-format motherboard - that's an industry
standard that just about everybody but people like Compaq adhere to quite
closely.

A new ATX-format motherboard should fit in the same ATX-format chassis. You
will probably need to swap out the thin metal plate where the keyboard and
port connectors are exposed, and you may need to add or subtract or move
some of the standoffs that the motherboard screws into. Some alterations of
the wiring to the front-panel switches and lights may be required.

2. What kind of RAM do I need for this combo.

At least 256 megs of whatever the new motherboard takes. If someone tries to
strong-arm you into 512 megs, and cash isn't excruciatingly tight, let him
have his way.

3. Can I use the same "C" drive meaning leave the old drive in with
it's operating system..XP Pro...

You can't swap motherboards willy-nilly and expect XP to boot with the new
motherboard. There's a blue screen (BSOD) that is well-known to occur -
0x0000007B as I recall, if the new motherboard differs too much from the old
one.

What is "differs too much"? Well swapping in a AMD CPU on a VIA or NVIDIA
chipset motherboard for an old Intel chipset motherboard is IME often "too
much". YMMV. There are some workarounds that are possible and can work out
great, because I've done what I just said might be impossible, a number of
times.

You'll have to reactivate XP because it will detect the changes and throw a
hissy-fit. MS will let you reactivate as a matter of policy, but you may
have to make a phone call. The goal is to convince the person at MS that
this is a true upgrade, and not a clone of one OS license onto two PCs.

However, if you replace a fairly new (2-3 year old) Intel chipset
motherboard with a brand new Intel chipset motherboard, you have a pretty
good chance of the machine getting through its first boot. Similarly, if you
replace a fairly new (2-3 year old) VIA/AMD chipset motherboard with a
brand new VIA/AMD chipset motherboard, you have a pretty good chance of the
machine getting through its first boot, as well.

I recommend that going into the swap, apply all the latest MS XP patches
and XP SP1, if you haven't already done so. Also, do a full Chkdsk and
Defrag of the hard drive with the old motherboard, unless it has become very
unstable.

You're usually coasting down hill after you get to the desktop on the first
boot. XP will then automatically tailor itself for the new motherboard. You
may have to use the new motherboard's driver disk to get complete support
for all the peripherals on the new motherboard. I can think of cases where
you might be able to smooth the process by loading all the drivers for the
new motherboard while the system is still running on the old motherboard,
but there are cases where the driver setup program won't allow this. Check
the new motherboard's documentation carefully.

how do I have to reset for the new MOBO/CPU.

XP will handle most of it automatically. It will probably handle enough
automatically so that you have enough of a working system to manually load
any drivers that XP doesn't handle automatically.

I know I need to get someone to do the work I'm not
qualified to do..I just want to get an idea what I need so I can
price out the upgrade.

If there is good planning and reasonable compatibility between the new and
old motherboards, a motherboard/CPU upgrade is no big deal - maybe an hour's
work. If things go wrong, the job may never be able to be completed *right*
and you're back down to doing a clean install. Always backup everything of
value before you touch the screwdriver the first time.