troubleshooting - Major Vista issues with multiple causes

I have a laptop running Windows Vista Home Edition. Recently (out of the blue -- no software or hardware changes) there have been many issues with the OS:

1. Logging in (as any user) sometimes does not work -- the welcome screen lasts until I do a hard shut down.


2. When logged in, the network icon in the notification area is unresponsive and indicates that there is no connection, even though the laptop connects to the internet just fine.


3. Most programs run fine, but Task Manager does not display (the CPU icon in the notification area shows up, but not the window) and Word 2007 freezes at the splashscreen.


4. After selecting Shut Down or Log off from the start menu, the computer gets stuck at the "Logging Off" screen until I do a hard shut down.

These problems persist (even in Safe Mode) until I do a system restore from the install disk to a previous, stable state. After the system restore, everything is back to normal, except that a few specific actions cause the OS to exhibit the same issues again (necessitating another system restore):

1. Shutting down off the start menu works fine, but on the next boot the problems are back. Logging off, then shutting down from the log-in screen works fine.


2. Putting the computer to sleep and then waking it up works, but on the next boot the problems are back.


3. Logging off while programs are running causes the problems to resume on the next boot.

I've run every hardware and software diagnostic (including a virus scan) I can think of, and I am reasonably sure that it is not any of the hardware.

Has anybody else experienced similar issues? Do you know what could be causing this, and what might fix it?

Thanks.

Details about the laptop:

• Model: HP Pavillion dv6775


• OS: Vista Home edition SP1 (32 bit)


• RAM: 3GB


• Video card: nVidia Geforce 8400M


• CPU: Intel T5450 (Core 2 Duo)

Answer

If you restored from reinstall CDs and you still exhibit problems, my guess would be the RAM has gone bad. Try this program to test the RAM:
http://www.memtest86.com/

If the RAM turn out fine, then it could be overheating, but that is just an educated guess.

My dad actually got 2 HPs to work on, both ironicly with the same exact problem (LCD issues). I would try to see if it is under warranty...if not and the RAM checks out and it doesn't seem to be overheating...I would cut your losses. Even my (HP) Compaq V2000 had an LCD issue.

Personally I would not buy an HP laptop. Get a Lenovo thinkpad, Dell, or so I can sound impartial...a Mac.