A new hard drive is a ridiculous thought. A reload of the OS is unlikely to help, although it's unlikely.
My guess: you need a better driver, and that has to come from Dell. Sleep and hibernate are tricky things for some devices.
If they can't supply a better drivere, the things to do are:
1. Reload the OS from the recovery partition, and see if that helps.
2. If not, call again. If no help, say the machine doesn't behave as it should, so either they should repair it under warranty. If they can't fix it, return the laptop and get your money back.
Kees
I have a new Dell laptop with Windows 7 that keeps dropping my wireless connection upon sleep/hibernate.
I spent 3 hours on the phone between Cisco and Dell. All of my drivers have been updated. Dell seems to think I need a new harddrive and OS reload.
I disabled "IP Helper" and that helped for about 12 hours. I have a second laptop running Windows XP and it experiences None of these problems.
Any suggestions?

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