Monitor goes black after login Vista HP?

I have a puzzle which I have no idea how to solve. Over the last few days if I shut down my Desktop PC, Vista HP with Quadcore and 3 gig of RAM then when I restart and click the logon icon (no password and I'm Administrator) after I get the welcome logo and the swirling blue circle the screen then goes black for around two minutes, I only have the mouse cursor visible. After that the machine bursts into life and loading completes and everything works fine. If I log on as another member of the family (again no password) then the machine burst into life straightaway. There is no new software or changes on the machine. If I select Ubuntu - dual booting then that is also fine.

I have found that if I disable UAC then the screen loads normally and likewise if I disable Aero the screen loads normally. The only process I can see that is using any amount of RAM (ctrl alt del works to bring up task manager) is dwm.exe which is taking approx 38500.

I am completely stumped as to what it can be - I have run virus scans spyware scans, run SFC scannow and that has come up clear. In every other respect the PC works fine - it's just an annoying anomaly that has appeared from nowhere.

I would firstly see what software you have loading at startup that the other accounts do not and also try removing the password and see what happens

- Pea0n

Pea0n said:

I would firstly see what software you have loading at startup that the other accounts do not and also try removing the password and see what happens

- Pea0n

Click to expand...

There are no passwords, only difference is I'm admin and others are standard users - msconfig shows 36 processes whichever user is logged though it does appear to be related to either UAC or Aero in some way. I have disabled Nvidia graphics and updated drivers etc. but nothing makes any difference.

Got anything connected to the S-Video ?.

Happened to me too, only my desktop never loaded. Just a black screen after logging in. Only way out was to CAD and reboot. Did this seemingly randomly. 8400GS Nvidia card.

Since reinstalled and it hasn't done it since. Pretty weird. Never found a solution.

theheyes said:

Happened to me too, only my desktop never loaded. Just a black screen after logging in. Only way out was to CAD and reboot. Did this seemingly randomly. 8400GS Nvidia card.

Since reinstalled and it hasn't done it since. Pretty weird. Never found a solution.

Click to expand...

Same card as mine, the odd thing is that when I have found other instances of this happening it always seems to be Nvidia and HP computers - same as I'm using? Don't have Svideo either.

I have a theory and wonder what others think - I found that if I wait once the log on icon appears for just one minute before clicking the log on icon that the screen loads straightaway. During this period I can see a lot of HD and router activity. I am wondering if the problem could be my AV scanning before it loads up - I am using AVG 8.0 Free.

Checked Dreamscene is enabled?

Random_23 said:

Checked Dreamscene is enabled?

Click to expand...

Dreamscene is a Vista Ultimate programme - not available to us lowly Home Premium users

Vista Premium here too, not that I think it makes much difference. The computer it happened on I built myself, although coincidentally a Q6600. I wasn't running any antivirus either.

I just chalked it down to one of those OS bugs. It was annoying, but it would have annoyed me a hell of a lot more had it been my main computer (as it was, it was just running folding@home so I seldom logged into it)

I’ve had to admit defeat in solving this log in puzzle as I’ve tried everything.

1. Uninstalling AV has no effect.
2. Switching off Firewall has no effect.
3. Disabling all start-up items in msconfig has no effect.
4. Providing maximum memory for boot up (3gig) has no effect.

Doing the following does work.

1. Log in as Standard User.
2. Wait for 50 seconds following appearance of log in icon before clicking it.
3. Boot up in safe mode.
4. Boot up in diagnostic mode.
5. Disable UAC.
6. Disable Aero.

It’s just as though the machine has booted to quick i.e. arrived at the log in icons before the machine has finished loading everything, hence waiting the extra 50 seconds finishes the job.

It's not the end of the world I know as I usually use Vista Sleep so rarely do a full shut down, it is however very annoying that I can't solve this riddle.

system specs?

i have a similar problem my nvidia 7xxx

Phatzy said:

system specs?

i have a similar problem my nvidia 7xxx

Click to expand...

OS Name Microsoft® Windows Vista™ Home Premium
Version 6.0.6001 Service Pack 1 Build 6001
Other OS Description Not Available
OS Manufacturer Microsoft Corporation
System Name System Manufacturer HP-Pavilion
System Model a6250.uk
System Type X86-based PC
Processor Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz, 2400 Mhz, 4 Core(s), 4 Logical Processor(s)
Boot Device \Device\HarddiskVolume1
Installed Physical Memory (RAM) 3.00 GB
Total Physical Memory 3.00 GB
Available Physical Memory 1.76 GB
Total Virtual Memory 6.22 GB
Available Virtual Memory 4.99 GB
Page File Space 3.29 GB
Name NVIDIA GeForce 8400 GS
Adapter Type GeForce 8400 GS, NVIDIA compatible
Adapter Description NVIDIA GeForce 8400 GS
Adapter RAM 256.00 MB (268,435,456 bytes)
Installed Drivers nvd3dum.dll,nvwgf2um.dll
Driver Version 7.15.11.6230
Resolution 1680 x 1050 x 59 hertz
Description Disk drive
Manufacturer (Standard disk drives)
Model WDC WD5000AAKS-00A7B0 ATA Device
Bytes/Sector 512
Media Loaded Yes
Media Type Fixed hard disk
Partitions 3
SCSI Bus 0
SCSI Logical Unit 0
SCSI Port 0
SCSI Target ID 1
Sectors/Track 63
Size 465.76 GB (500,105,249,280 bytes)

Description Disk drive
Manufacturer (Standard disk drives)
Model WDC WD5000AAKS-65YGA0 ATA Device
Bytes/Sector 512
Media Loaded Yes
Media Type Fixed hard disk
Size 465.76 GB (500,105,249,280 bytes)

Got exactly the same problem here.

Shuttle with Vista Ultimate. I've taken to hibernating it to get around it but everytime I do a real reboot the only thing that'll get me back in is a last known good

CrimsonAvenger said:

Got exactly the same problem here.

Shuttle with Vista Ultimate. I've taken to hibernating it to get around it but everytime I do a real reboot the only thing that'll get me back in is a last known good

Click to expand...

I use Vista Sleep 99% of the time and only use full reboot if installing software, updates, booting into Linux etc. so not the end of the world but annoying no less. If I wait just 50 seconds after the startup icon appears then boot up is normal. This issue has only presented itself over the last couple of weeks so suspect an update may be to blame.

I'd be tempted to just nuke whatever graphics driver I had and then reinstall it.

theheyes said:

I'd be tempted to just nuke whatever graphics driver I had and then reinstall it.

Click to expand...

Done it, rolled back, uninstalled, updated from Nvidia web site and not made one tat worth of difference. I suppose for the odd few times that a do a full reboot instead of using Vista Sleep I'll just have to live with it.

Full format?

ticktock said:

Full format?

Click to expand...

You've lost me there, what do you mean full format????

There is also the other issue of if it was just graphics then why would disabling UAC cure the problem, as does switching off Aero?

Most people that have had this problem have came to the conclusion that it is something to do with their antivirus software.

Some have mentioned that it happened after an antivirus update

which antivirus software are you using, perhaps disable and restart PC see what happens or uninstall alltogether and see