Windows XP won't recognize new HDs

So you have installed a new empty HDD in your system and connected power and data cables to it. Further, you report that the BIOS does "see" it. What I do not see is any mention of Initializing it. That is necessary before your OS can use it.

You can check for the new HDD in the Windows utility Disk Management, but you need to know where to look. In Disk Management on the right are two panes. The upper one shows you all the storage devices that Windows does understand and can use. The lower one lists those PLUS any other devices that BIOS recgnizes and reports, but Windows does not understand yet. Both of these panes SCROLLS so you can see all they contain. So, go the the LOWER right pane and scroll down in it until the new HDD shows up. It will show as a single rectangle of Unallocated Space.

Now, once you have confirmed that the hardware device is detected (but useless to Windows so far), you can proceed with the cloning operation. That process will do all of the necessary work of Partitioning and Formatting the HDD for you before it carries out the data cloning. So, back out of Disk Management.

Now you run the cloning tool. Make VERY sure that, as you start it up, you identify the old C: drive unit as the SOURCE device, and the new HDD as the DESTINATION device. It will show you a recommended set of parameters for preparing the HDD for the operation. Do NOT merely hit "Enter" without looking at that info. In particular, MANY cloners I have seen default to making the Partition on the Destination drive the SAME size as the original Source unit, and very often that is NOT what you want. Often the new drive is larger and you want to use all of its space. If you want to set this up some way that is NOT the same as the default setting shown, you need to use a menu system to change the configuration.

There can be a "catch" here. IF your NEW HDD is larger than 2 TB, you can only use all of its space if it is partitioned using the newer GPT system, not the older MBR system. BUT you can only boot from a HDD with a GPT Partition if the mobo has UEFI Support in its BIOS. Moreover, in the specific case of Win XP, I do not think it has a device driver that can use a GPT Partition to boot from. So, unless you can sort out those things, make sure that the Partition type being created is MBR. Of course, if the HDD is not over 2 TB, you are always best to specify the MBR system anyway.

The MBR system will limit you to a size of no more than 2 TB. But within that limit, set the new Partition to be as large as you like, up to the HDD's capacity. Make sure it is set to make this Partition a BOOTABLE partition. For Formatting options the defaults probably are correct - use the NTFS File System and do a Full Format. When you have all the parameters set, tell it to proceed. The Partitioning and Formatting steps will probably take a few hours, and then the copying of data for creating the clone will take more time again. So be patient.

When the entire operation is complete, back out of the cloning software and shut down. Now do a little cable switch. Disconnect the power and data cables from the old drive. (You might opt to leave it in the case temporarily until you have verified that the new drive is doing all you need.) Now change the way the new drive is plugged into the mobo SATA ports. Plug it into the SAME mobo port as the old drive was using. Then close up and turn on. The system will look at that particular SATA port for the boot device and WILL find one there, so it should boot cleanly. After you have used the system and are convinced everything got cloned properly, you can go back and physically remove the old HDD and deposit it in its proper final resting place.