computer has got slower & slower to start up

Hi my win 7ultimate 64B with a gigabyte Ep41T-UD3L MB has slowler & slower starting up from a cold start
Takes up to 30M to even get to bios
But If tumned off for no more than 5mins, starts OK immediately I have tried different memory slots but no difference
There is also a slight whine from the inbuilt speaker
Help??

If you boot off a usb or cd/dvd when cold does it start quickly without the whine? I'm thinking it may be HD issue if it's a spinner.

Work through the hardware tests, infection scans, SFC, establish a Clean Boot, resolve repeat errors - all from the Troubleshooting Steps for Windows 7.

Compare the install you have with the perfect install in Clean Reinstall Windows 7 because in the same amount of time you can have the best install one could possibly have just like 1.3 million others who have followed those steps without a single complaint. http://www.sevenforums.com/tutorials/220165-troubleshooting-steps-windows-7-a.html