Could be hardware, could be software. One would tend to lean towards
software since doing the "last good startup" works but that might also be
misleading and be caused by a failing power supply (for one ex.).
The First Question Of Troubleshooting: what changed between the time things
worked and the time they didn't?
Some suggestions to try and narrow down the cause:
1. Answer The First Question and act accordingly.
2. Boot directly into Safe Mode. Does this work? If yes, then you know
something starting with Windows is causing the issue.
2a. Update all drivers. See below for general drivers information.
2b. Manage Startup matrix and possibly do a clean boot. See below for
information on that.
3. If booting directly into Safe Mode doesn't work and/or the software
troubleshooting doesn't help, do hardware troubleshooting.
http://www.elephantboycomputers.com/page2.html#Hardware_Tshoot
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General drivers information - The First Law of Driver Updates is "if it
ain't broke, don't fix it". Normally if everything is working you want to
leave things as they are. The exception is that heavy-duty gamers will
usually want to update their video and sound drivers to squeeze every last
bit of performance out of the hardware to get the fastest frame rates. If
you're not one of those people, you don't need to update your drivers if
there are no problems you are trying to solve.
Never get drivers from Windows Update. Get them from:
1. The device mftr.'s website; OR
2. The motherboard mftr.'s website if hardware is onboard; OR
3. The OEM's website for your specific machine if you have an OEM computer
(HP, Dell, Sony, etc.).
Read the installation instructions on the website where you get the drivers.
To find out what hardware is in your computer:
1. Read any documentation you got when you bought the computer.
2. If the computer is OEM, go to the OEM's website for your specific model
machine and look at the specs (you'll be there to get the drivers anyway)
3. Download, install and run a free system inventory program like Belarc
Advisor or System Information for Windows.
http://www.belarc.com/free_download.html - Belarc Advisor
http://www.gtopala.com/ - System Information for Windows
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Manage Startup matrix/clean boot - Start Orb>Start Search box>msconfig
[enter]
If you are prompted for an administrator password or for a confirmation,
type the password, or click Continue. Then see what is on the Startup tab.
You don't need to restart immediately, but the next time you do you'll get
a dialog saying you've used the Utility. Usually in Vista this will be
blocked by Windows Defender and you'll need to allow it so you can then
tick the box that says in effect, "don't bother me about this again".
Important - Do not use the System Configuration Utility to stop processes.
Instead, use Start>Run>services.msc [enter] and do not stop any services
unless you really, really know what you're doing.
The free Autoruns program is very useful for managing your Startup -
http://www.microsoft.com/technet/sysinternals/default.mspx - Autoruns
How to troubleshoot a problem by performing a clean boot in Windows Vista -
http://support.microsoft.com/default.aspx?scid=kb;EN-US;929135
*****
Malke
