the operating system at this time? Is it on the same drive that it was originally???
Your 120 GB drive is probably a 7200 RPM unit thus some more noise [not such as you describe though].
Did your BIOS actually see the new 120 GB drive??? Very possible that it won't see a drive that large.
The large screen icons are probably simply that the system installed the default MS VGA drivers. This can be resolved after we get the drive issues cleared up.
What make is the hard drive??? What IDE port is it on?? Is it jumpered properly for the port and its position [Master or slave]?
You probably have a restore disk from HP. Why not start by taking the 120 GB drive out and see if you can get the system working in its original configuration???
Keep all of your answers in this thread so that everyone can see what has been advised, what youm have tried and the results. The thread will percolate to the top of the list whenever a new entry is made.
I installed a hard drive over the thanksgiving weekend that I got from best buy (120gb). My system is an HP with a 1.3 gz athlon. 1 gb ram. I also have a cd rom, cd writer, 64mb nVidia graphics card, the 40gb hard drive that came with the system and a floppy drive. When I installed the hard drive the system started up, but it was alot louder than before. Before it was loud but this was slightly louder. The 120gb hard drive was replacing a 7gb hard drive I had.
Then I shut down the system and tried starting it back up again, but to no avail. I saw one of the fans moving slow, so I unhooked the new hard drive and it seemed faster. I couldn't get the computer to load with the nVidia card, only go to the windows xp home loading screen and then the monitor would go blank. Turning the monitor off and back on gave me a message that said no input was being received. So I put the monitor on the original port that came with the computer and that got me to the windows desktop, but everything was bigger and no taskbar, I think it was still loading. I restarted and no all I can get is to the loading screen again, but then it goes blank after that, the monitor stays on though but still blank.
I got a 300 watt power supply, and it was the right height and width but too long. The one that came with the system was small and attached to something to make it fit width and height wise. I had to take it back. I unhooked the cd rom, the new hard drive and the floppy drive, but it still won't work. I have no idea what could be the problem unless it really was the power supply at first and the low power damaged something. If anyone knows what might be wrong let me know. Also if I take it to a computer shop to get it fixed, how much should I expect to spend? This will help me determine if it would be better just to buy a new computer.

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