Bigger hard drives are inexpensive these days. You can find good 300GB internal HD for less than USD$100.
If you go over 137GB, then you have to watch for for 48-bit compatibility issues.
1. system BIOS must support it
2. Windows XP must have SP1 or later
More info: 48bitlba.com
If your BIOS version is earlier than ''A03'' (Release Date: 2/26/2002) then you need to download and install the latest FlashBIOS update from http://support.dell.com. This will give you support for those larger HD's.
I'd get the ATA/100 or ATA/133 HD with at least 8MB cache and 7200rpm that meets my budget.
NOTE: Your system is too old to take a SATA HD without adding a PCI hard disk controller card.
Dell Dimension 4400, WD 120GB, XP, P4, 640 RAM
The smoke damaged my hard drive. It has failed the WD Diagnostic SMART test. I also did the 10:30 hour extended test--which it also failed. I was advised to back up my data and buy a new drive.
My Dell system is 4 years old. My insurance company says they figure 6 years for the life of a pc.
I can't decide if I should buy another 120GB drive or splurge and get a bigger drive.
Any pros and cons?

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