Here is the support site for the
HP Pavilion 553x desktop.
It comes with an Intel Pentium IV 2.00 GHz processor and 256 MB of DDR RAM and Intel 845 integrated graphics and a 40 GB hard drive.
It came with the original release of Windows XP Home Edition, so I'm guessing it was manufactured on or about 2002.
Unless you maxed it out with 2 GB of RAM and upgraded to a NVIDIA video card that supports Windows 7, it was a waste of time upgrading it from Windows XP to Windows 7.
As long as you don't load the computer with a lot of personal data(games, music, videos, etc.), a 40 GB hard drive has sufficient free space to run Windows 7.
I've upgraded a few older desktops to Windows 7, so I'm speaking from experience.
It appears that you may still be able to purchase the recovery disc kit for it from
here.
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