I've posted a couple of other things in this forum in the past week. Thanks to all that have answered.

I now have big trouble. From the beginning for those just tuning in:
I have a 20GB HD, and a 40GB HD. I've cleared off the 20 - used before, and a known good drive, and want to partition it to be the main program/OS disk(s). I want to run Win XP Pro and Red Hat 7

Only 1.8GB is being recognized, after a number of attempts and re-formats. At one point I thought I had it, since fdisk recognized that it was, in fact, a 20GB drive, but would only let me make 2.4 GB partitions. (I need to split it in half)

The Windows XP that I loaded on a FAT32 partition ( Yeah, I know. That's why I started over) is gone. And I gave up on downloading Mandrake and got an actual manufactured CD distro of Red Hat 7 (in a ___ For Dummies book. Helps me not at all).

Here's what I want to know. Using the DOS utilities (or something else), how can I get the full drive to be recognized? (It's a Maxtor drive, and I can set it up as a 20GB divided into 2 10GB partitions under the Maxtor utilities that came with it, but Windows and fdisk/format will still only recognize 1.8GB on one partition after that.)

Can someone talk me through partitioning/formatting that 20GB drive properly to dual boot Win XP Pro and Red Hat 7? Or point me to a website that has real information on it?

I've done this before (for Windows), but I'm now extraordinarily frustrated with the whole thing.

My life is falling apart over this... OK not literally, but I have work that lives on that system, and it's about to start costing me money. If it's going to cost me jobs, then it does not need to be there...

Did you answer Y to a question something about supporting large size disk when you start the fdisk ?

(AFAIK) you need to answer Y to be able to make a FAT32 partition which supports more than 2 GB partition size.

If that doesn't work, have you ever try to reconfigure you HD at BIOS setup ?

It should work OK when you make FAT32 LBA partition. When you run Linux fdisk and press 'l' you'll see a list of possible partition types. Note that 'b' is FAT32 and 'c' is FAT32(LBA). You need the second type.
When you say 'Y' to the question about large disks in DOS/Windows version of fdisk, the 'c' type will be created (AFAIK).

does you bios support large disks and has it identified it correctly?

if it has not you can download a program from the manufacturer, maxtor has a program that does it, sits before the bootloader and loads before lilo etc and paches over the bios hard disk address

i have found that if you just empty your drive of all partitions then run the XP setup thing and it should ask you what size partition you want tell it you want half the disk, then when xp has finnished install linux and depending on the install program it should find this space and auto allocate space for your / and swap space

and lilo gos on last so it sits before the XP bootloader

Say yes to LBA

Check bios for full size (mine once got changed by windows somehow with a dual boot setup)

fdisk /mbr to clear the MBR.

THEN:
Make a windows partition using windows Fdisk.
Install
Run linux installer.
Config LILO to boot windows.

have fun!

lopoetve: what is that LBA option for!??

First udate your bios (flash) maxtor has free programs to partion new drives easy to use or you need partion magic.

I've done just what you're doing a couple of times... in fact my system is currently set up just that way. I did the following:

1. Start from scratch. Fdisk to delete all old partitions. Re-partition the drive using the desired size for the Windows partition. I used 50%. DO NOTHING with the remaining space DO NOT create a logical partition.
2. Install and configure Windows normally.
3. Install desired flavour of Linux as you normally would. Linux will detect the unused, unpartitioned space and offer to set up on that space. Let it. Linux setup will do all the necessary partitioning and formatting for it's own partition all by itself without disturbing the Windows partition.
4. When you're done Windows will be an option on the Linux Boot-Loader.

Hope this helps
Mike