A customer asked me to upgrade three PCs from XP to win7. I purchased three windows 7 pro licenses.
The machines are Asus P4 3Ghz with 1 or 2 Gb RAM, 160Gb hard drives and PCI-E Radeon X550 SE DVI/VGA 256Mb graphics cards.
The first one has 2Gb RAM, installed without a problem and is running well.
I've installed win7 three times on the second one which has 1Gb RAM and each time hit the same black screen issue.
Win7 installs correctly. The first time, I installed Office 2007, printers and other applications, checked all was well and left it for the users. I did not apply any windows updates as I expected them to run automatically. (Same with the first machine which did not have a problem)
They rang the next day to say they had a black screen on the second PC.
When I looked at it I found it would switch on, but after the BIOS - nothing, no disk activity. The caps lock led would go on and off with the key, but Ctrl-Alt-Del immediately restarted the machine. F8 had no effect. BIOS access is fine.
I ran memtest and a disk test but found no problems.
I restarted with the win7 disk startup repair and tried going back to checkpoints. It was clear from the checkpoints that windows updates had happened overnight.
However, despite going back to each checkpoint up to the first one, prior to any updates, I was still unable to start windows. The restores gave me 0x8000fff failures and the message "a patch is preventing the system from starting - system restore error 0x490"
Next I replaced the radeon card with another and tried again, reinstalled win7 from scratch
Two windows updates came through and I applied them and restarted - back to the black screen and no way out.
Using the command shell from windows recovery, I ran chkdsk /r /f but found no problems - same black screen on normal restart
In the command shell again, having googled some possible issues, I renamed SoftwareDistribution as SDOLD
There was no windows\winsxs\pending.xml
I also checked the registry in HKLM\Components - the suggested keys AdvancedInstallerNeedsResolving and PendingXMLIdentification were not present.
Then I reverted back to the original Radeon card (no problems at all with it during installation)
Installed win7 for a third time, without any other software, anti-virus, printers etc - just the basic installation and internet access through the company router. Then installed the two patches I was presented with - windows update agent 7.6.7600.256 and security update for windows 8 KB2621440 - Restarted and booted windows correctly
So far, so good. I then went to windows update on the control panel and found 108 updates due, I selected and downloaded them all.
At the end of the updates, I looked through the list and found them all either 'successful' or 'pending'
Restart - BLACK SCREEN AGAIN!!!
One thing I did notice was that despite clearing all partitions from the HD, the windows installer created two partitions.
When I used windows system recovery from the dvd, windows was on the second D: drive, not the first.
I used diskpart to select the second partition and set it active. However, this made no difference on restart.
At this point I have not touched the third machine which still has a working copy of XP on it. I don't want to until the second machine is working.