Make sure your Hard Drive and Dvd writer are set to DMA mode in device manager by doing the following..
Go into your Control Panel by first clicking on the Start Button.
Then click on Settings, then Control Panel.
Then double click on the System icon to open up the System Properties window.
Now click on the Hardware tab located at the top of the screen.
Then click on the Device Manager button in the center area of the screen.
Now click on the plus sign [+] next to the IDE ATA/ATAPI controllers to expand that section.
Then double click on the Primary IDE Channel to display the Primary IDE Properties window.
Then click on the Advanced Settings Tab at the top of the screen.
Now for Device 0, ensure that the Transfer Mode: selection is set to DMA if available.
Then for Device 1, ensure that the Transfer Mode: selection is also set to DMA if available.
Then click on the OK button at the bottom of the screen to save your settings.
Then double click on the Secondary IDE Channel to display the Secondary IDE Properties window.
Then click on the Advanced Settings Tab at the top of the screen.
Now for Device 0, ensure that the Transfer Mode: selection is set to DMA if available.
Then for Device 1, ensure that the Transfer Mode: selection is also set to DMA if available.
Then click on the OK button at the bottom of the screen to save your settings.
Then close Device Manager and the Control Panel to return back to your Windows session.
Was your system Ok before you reformatted?...or have you been inside your case tinkering recently?...Post back if still unresolved.