Hi everyone,

Back with another computer problem.

So after much aggravation after my HDD failure a couple months ago, trying to get XP running in spite of not being able to find my disks, I finally bit the bullet a few weeks ago and bought Windows 7. Everything installed fine, but a few days in I started getting problems with the computer needing to be rebooted multiple times coming out of hibernate (fixed by disabling hibernate) and constant failures of the video driver - screen would blank out a couple times and then come back with an error message telling me the video driver had failed and recovered. Also been having some trouble with DVDs locking everything up.

So last night, I got stuck in this nasty reboot loop. Every time it tries to start up, after the Windows splash screen, it reboots and wants to try the repair function. I've tried that, but it fails every time. I've Googled this error and tried a few things - switched AHCI/IDE setting in BIOS, disabled C1E, tested memory through Windows and found no errors. When booting in safe mode, it hangs at classpnp.sys.

I'm wondering what the chances are that this could all be a video card issue. I'm thinking it wouldn't hurt to have an upgrade anyway, so I could pick up a relatively cheap one and see if that helps.

I'm currently set up with an ASUS P5K-E, Intel Q6600 2.4 GHz CPU, 8600 GTS 256 MB Video Card, 4 GB RAM.

Is there anything simpler I should be trying, is there a decent chance it's the video card, and would one of these be a noticeable upgrade?

http://www.ncix.com/products/?sku=64...anufacture=XFX

http://www.ncix.com/products/?sku=64...anufacture=XFX

http://www.ncix.com/products/?sku=64...X&promoid=1078

Just to add to this, seeing RDH's thread reminded me of the suggestion to unplug everything and try firing it up - I did this with all my USB devices, and no luck. There was also a suggestion to unplug cards, but I haven't cracked the case to do this yet.

What puzzles me is that I haven't made any changes. I added 2 GB of memory, but that was several days ago, and it hadn't been causing any problems. I don't think there have been any Windows updates recently, but I don't know that one of those could cause the problem anyway.

That's what left me thinking video card. Since I was having some sporadic issues with it already, maybe some component has finally given way for good. It seems to work - I see the POST screen, and the Windows splash screen, but perhaps something could be wrong and still allow it to operate before it hangs the system. IDK. Help!

If I were in your shoes I'd remove the RAM you recently added, and while you have the case opened make sure everything inside is seated/connected firmly.

Power it up and see what happens. If it boots then add the RAM back in and power it on again and see what happens.

It's worth spending a little time on this before going down the path of replacing the video card.

Yeah, I'll probably try that and some other tinkering. I had already been thinking about a video card anyway, which is why I was considering going that route.

Any other thoughts or suggestions?

First of all, the culprit doesn't come from classpnp.sys directly. It is very very likely your GPU driver is causing these issues which might come from faulty hardware.

First step, start into safe mode with command prompt, I'm fairly certain this will allow to boot into safe mode already in your situation if your GPU isn't roasted already.

In safemode just uninstall the GPU driver completely via device manager.

If your desktop/task bar won't load you can do that via cmd as well.

That's the thing with this loop - you can't start Windows in any mode. I just tried safe mode with the command prompt, and got the same result. Hangs at classpnp.sys, then restarts about 15-20 seconds later.

As we can't get any logs from your system, we have to consider a lot of eventualities.
What the error means is basically windows is in the process of checking if every hardware component works as intended, obviously it's not in your case and windows should proceed to repair any glitches but fails miserably at it, as usual.

Still could be a lot of things, even if a roasted GPU makes sense in your case, it could just be some bad sectors on the HDD who screwed up the classpnp.sys.

There's some workarounds.

1) Run sfc/scannow from your win7 dvd http://www.sevenforums.com/tutorials...ompt-boot.html

2) Load failsafe defaults/reset bios.

3) Get the classpnp.sys from your exact OS version from a really trusted source. Just use another computer or have a trustworthy contact send it to you. Do not download it from anywhere.
Get www.knoppix.org , burn it to a DVD and boot a fully functional, live version of Linux to replace the files in windows. (It's really easy, NTFS drives are auto-mounted with one click)

You can also use it to access your HDD and make backups to a dvd/thumb drive prior to reinstalling windows.

In case you know your way around linux a little you can also use it to detect and troubleshoot any hardware issues.

4) Reinstall windows

I assume step 1 is going to be different from the Windows Repair option I keep getting and have already done a few times?

As for the HDD, seeing as it's an SSD I installed a couple of months ago, I'd hope not, but I guess it's possible. Not sure how common that is on SSDs.

I've only had this version of Windows installed and running for a couple of weeks, which means reinstalling isn't going to be a huge ordeal, so I'd probably skip 3 and go right to 4. The only reason I haven't just gone ahead and done this already is that I'm assuming there's an underlying problem here I'd like to get to the bottom of rather than reinstalling Windows and then having this happen again 2 weeks later.

Given that I was having constant graphics driver problems before this happened, it seems that if I reinstall/repair Windows, and my GPU is fine, at the very least I'm probably going to have to play around with different versions of the drivers to find a stable one. This is what got me to thinking about getting a new video card - I'd rather spend a little money for a bit of a speed boost as well rather than **** around for hours trying to find a driver that works. Or am I thinking about this all wrong?

Thanks for the suggestions so far!

Wait, you got a SSD and changed the AHCI settings in Bios?
That changes a whole lot.

Was it set to AHCI/Raid or IDE to start with?

Basically it has to be set to AHCI/Raid or the disk controller will get mental and also TRIM won't work without it on most controllers, which essentially means your SSD isn't going to last as long as it could and won't ever perform as good as it could.

Setting it up with AHCI usually means you got the driver on a thumb drive and implement it during the win7 install as windows needs the driver during the installation already in order to be able to even access the drive.

If it's not a big deal, I'd highly recommend a fresh install of windows.

1. Prepare your AHCI driver (manufacturers page)
2. Install windows
3. Install chipset drivers from the cd that came with your motherboard.
4. Install GPU drivers (most current)
5. Update windows until there is no more updates.
6. Update your chipset drivers manually
7. Make backups

Pretty sure it was AHCI when the problem happened, and I tried switching it to IDE; nothing changed.

When you say "prepare your AHCI driver", what does that entail? I don't think I did anything with drivers when I first installed it.

Edit to add: Unlike when I reinstalled XP, I also didn't install any of my motherboard/chipset drivers, as Windows seemed to get everything set up on its own. The CD wouldn't have Windows 7 drivers since I put this computer together in February 2008, but I could of course see what they have online.

By preparing your AHCI driver I mean burning it to a dvd/floppy/thumb drive.
Windows really needs it prior to the install process in order to be able to assess everything correctly.
At some point during the installation you get the option to provide a source for the driver by pressing F6.

If you're happy with the standard AHCI driver windows provides (depending on the SSD you might become very unhappy with the driver or it will be just perfect, your manufacturer knows best, windows driver is fine usually) you can change it after installing windows a little more comfortably.

http://www.sevenforums.com/tutorials...s-7-vista.html

And to keep it short, a computer without chipset drivers can't possibly work without trouble.

Use vista/xp drivers if there's no other option, that doesn't make any difference usually but you must install chipset drivers.
That applies to every kind of computer.

TYVM. I'm going away on Saturday for a couple of weeks, so I think I'm going to hold off until I return, but I'll try a Windows reinstall when I get back with your instructions re: drivers.