Here’s what you need to know about the so-called Black Screen of Death: There’s no such thing.
Yes, yes, I know: The mainstream and tech press published hundreds of stories last week using that term to describe a supposedly new phenomenon affecting Windows PCs. Virtually all of those stories were rehashes of sloppy reporting based on a blog post from a minor security company that later admitted it was wrong and apologized for the story. But as I explain in this post, startup problems are not new to PC hardware and operating systems, and the phenomenon definitely isn’t limited to the Windows operating system.
Editors at tech sites love to write “Black screen of death,” because it echoes the well-known “Blue Screen of Death,” or BSOD—a dreaded event in any Windows user’s workday, to be sure. But it’s not a fair comparison: that distinctive blue screen is not a bug, it's a feature, more properly known as a STOP error. STOP errors allow Windows to respond to a catastrophic hardware or software failure that prevents the system from continuing to operate. A STOP error captures diagnostic information about the source of the failure and displays it as white text on a blue background. If you see a BSOD, there are debugging tools and well-documented troubleshooting techniques you can use to resolve it.
By contrast, when your PC or Mac torments you with a black screen (or, more accurately, a blank screen), all you know for sure is that the startup process failed at some point. Unlike with a BSOD, there’s no crash file to analyze, no tools you can use to figure out the root cause. The first step in the troubleshooting process involves figuring out where the problem lies, which can be anywhere in the chain of events that begins when you push the power button. It might be a bad system configuration, faulty hardware, defective third-party software, a buggy driver, a race condition or hang in a system service, corruption in the file system or registry, or malware.
So what does it mean if you start your PC or Mac and end up staring at a blank screen instead of seeing your familiar user environment? If you’re using Windows Vista or Windows 7, there are some known causes that I’ll list later in this post. But first, I want to dispel the myth that this sort of trouble is widespread, new, or unique to Windows.
The phenomenon I’m talking about here is not new, and it’s not limited to Windows PCs. That pesky blank (or black, or gray, or light blue) screen can occur with any operating system. A Wikipedia page suggests that the term was coined in 1991 by a technician deploying Windows 3.0; the same page notes with dry understatement, “The black screen of death has been present in all versions of OS/2.”
In the week or so since the current hysteria began, I’ve received a handful of reports from readers suggesting they’re experiencing this problem. In all three cases I did some remote troubleshooting and was able to determine that the problem was related to hardware. This lengthy but off-topic thread at a Microsoft-run forum for notebook and Tablet PC developers, which started in March 2008 and still flickers back to life every so often, shows the phenomenon in action. Most of the participants describe getting stuck at a black screen on a PC with with Windows Vista installed. But there are at least four separate problems described in the reports there.
The most interesting one involved a hardware defect with a large number of HP Pavilion (DV2000, DV6000, and DV9000) and Compaq Presario (V3000 and V6000) notebooks. The problem was related to overheating of defective NVIDIA GPUs, and was acknowledged in a late-2007 “Limited Warranty Service Enhancement” in which HP offered free replacements and doubled the normal warranty on affected systems. Dell offered a similar warranty extension on notebooks that it sold with the same defective part.
Depending on the root cause, problems with a blank or black screen can often be cured in less drastic fashion: by doing a hardware reset, using the Windows System Restore and Startup Repair utilities, or booting into Safe Mode and resetting a defective video driver configuration. I found several known “black screen” issues with Windows 7 and Windows Vista documented in the Knowledge Base; these are all fixed with hotfixes, stability/reliability updates. or service packs. (My full troubleshooting list begins on page 3.) It’s entirely possible, even likely, that similar unpatched issues are out there waiting to be fixed.
There’s no evidence that any of these issues are widespread at the present time or that a new issue is to blame for them. Microsoft says it’s seen nothing in its Product Support system to suggest this is a significant issue. That judgment has been confirmed by third parties as well. Graham Cluley, Senior Technology Consultant at security firm Sophos, wrote last week that “we [haven’t] had any reports from customers” of black-screen issues.
As I researched reports of blank or black screens at startup, I was struck by the similarities between Windows and OS X, where the same exact problems (and similar solutions) appear on support sites. In September of this year, after Snow Leopard was released, Apple support forums lit up with cries for help from users reporting that they had encountered a “black screen” at startup or during operation. Many of those user reports, ironically, use the phrase “black screen of death.” Apple has officially acknowledged the issues with a pair of support bulletins, titled Mac OS X: Gray screen appears during startup and Mac OS X v10.6: Gray screen after installing Snow Leopard. A companion help page lists what to do If you see a blue screen at startup (“you may have a problem with damaged or incompatible startup items or software”). The last two items on the list of five suggested remedies involve repairing your hard disk or (gasp) reinstalling Mac OS X. Oddly, the “I’m a Mac” guy never mentions that this might be necessary.
OS X “black screen” reports aren't new, and like the Windows variety they occur for all sorts of reasons. An official Apple support document lists startup sequences and error codes for Intel-based Macs. It notes that a “black screen” can be caused by a POST or BootROM failure. If the kernel fails to hand itself off to launchd, you get a “grey screen with Metallic Apple and spinning gear.” A blue screen means that the login process failed. Another troubleshooting topic, last revised in June 2009, explains what to do if your Apple notebook's display has no picture after you turn it on. You might need to reset the PRAM or the System Management Controller (SMC), which is explained in yet another support article.
A wave of incidents similar to the September Snow Leopard wave happened in mid-2006 with the 10.4.7 update to OS X, as documented in a pair of Apple support bulletins:
- MacBook: Vertical lines or solid gray, white, or black screen after updating to Mac OS X 10.4.7
- iMac (17-inch Mid 2006) starts up to black screen or no video
A troubleshooting article at Apple’s support site explains how to resolve startup issues in OS X 10.4 or earlier, which includes this description: “Your computer starts but either it won't reach the login screen, or it may reach the login screen but not load the Desktop after you log in… “ For OS X 10.3.9 and earlier, Apple devoted an entire troubleshooting topic to the issue, starting with this text, which sounds like the sort of thing you would think only applied to the “I’m a PC” guy:
Nothing can be more frustrating than turning on your Mac only to find that it won't start up. Instead of seeing the Finder, you see a blue or gray screen, an icon of a broken folder, a kernel panic, a flashing question mark, or a computer that just sits there. What can you do? Don't worry. It could be a simple issue that you can fix yourself...
The list of symptoms mentions an “empty, blue screen” and a “blank, gray screen.”
Black, blue, gray. It’s nice to know Mac and PC have something in common.
And don’t get cocky just because you use Ubuntu or some other Linux distro. I mean, the fact that the official Ubuntu Wiki has an entire section dedicated to Troubleshooting Blank Screen Issues might suggest that it is capable of suffering from the same woes as other operating systems, right? I found plenty of posts pleading for help with “black screen of death” issues in Ubuntu forums.
If you’re experiencing problems with a Windows PC that refuses to start up properly after it previously worked fine, your starting point should be the hardware manufacturer’s web site. In some cases, the issue is tied to a specific hardware model or family. For example, Windows 7 has been known to lock up or display a black screen on a Dell Vostro 1320, 1520, or 1720 notebook; the problem is caused by a resource conflict between the touchpad and the video BIOS, and can be fixed with a BIOS update. A more general article, published in August 2009, describes how to resolve blank-screen issues with a video driver update.
For notebook owners, HP has a document that decodes Blank Screen LED Error Codes. Another support document explains How to Troubleshoot Problems When a Computer Does Not Start Up or Boot Properly, which in turn links to more detailed diagnostic checklists for different stages of the startup process. One of those documents includes a list of specific black-screen errors and advice for troubleshooting errors where the system “may appear to stop responding with an empty, black screen.” Gateway has general troubleshooting documents as well: My notebook does not power on and Notebook – No POST / No Video.
From these documents and from my own experience, I’ve put together a brief checklist of things you might want to look for.
System won’t power on at all
In this scenario, the system is plugged in and you see lights indicating that it’s receiving power, but pressing the power button has no effect. The problem might be related to power management. Your first troubleshooting step should be to perform a hard reset of the system. Disconnect all external devices and unplug the AC power cord (remove the battery from a portable PC as well). Wait 10 seconds or so and then plug in the AC power cord and press and hold the power button for at least five seconds. If the PC still doesn’t start up, you have a serious hardware problem, possibly a bad power supply or a failed motherboard. If you hear hard disk noises and beeps that suggest the system is starting up but nothing appears on the screen, you might have a failed video card or monitor.
System powers on but won’t boot from installed operating system
If you’re able to watch system messages during the Power On Self Test (POST) routine but the system seems to stop responding before you get to the Windows logo or to a login screen, there might be problems with the startup files on your hard disk, or a recent configuration change (software or driver) might have interfered with the ability of the shell to load. To troubleshoot, try booting from the Windows installation disk or a system repair disk. Both Windows Vista and Windows 7 include a Startup Repair option that checks for common startup issues and automatically fixes registry corruption, missing or damaged system and driver files, disk or file system metadata corruption, errors in boot configuration data, and incompatible drivers or updates. It can also detect memory and hard disk errors, although it can’t repair them.
If you can’t boot from the installation media or a repair disk, you probably have a hardware problem.
Windows loads, but you get a black screen when you try to log in
This type of error might indicate a problem with your user profile. The second option on the System Recovery menu, System Restore, can roll back recent changes to a known good state, which might allow you to log on. If all else fails, try to start in Safe Mode and create a new user profile. If the new profile works, you can copy your data from the old profile and get back in business fairly quickly.
Known issues for Windows 7 and Windows Vista
If you’ve made it this far, you can also check for documented issues with your version of Windows. Here's a list of documented issues I've found for Windows 7 and Windows Vista:
For Windows 7, your computer might stop responding at a black screen if a screen saver is set to activate in the same time as the system is set to sleep. A hotfix is available. There's also a cumulative stability and reliability update for Windows 7 that corrects a variety of black-screen issues, including one that occurs when the computer resumes from hibernation.
For Windows Vista, with three years of history, the list of issues is much longer. If you upgraded a Lenovo computer to Windows Vista from Windows XP, the Onekey Recovery program could result in black screen. Another issue caused Vista systems to stop responding (hang) at a black screen because of file system corruption within the $Txf directory. You might also experience a black screen with an 0xc0000034 error message after installing a Windows Vista service pack.
When a volume on the hard disk is corrupted, a conflict between the Autochk.exe application and the NTFS system causes the system to reboot repeatedly and eventually stops responding with a black screen. The recovery process is complicated. Fortunately, a hotfix was published shortly after the issue was discovered and is presumably incorporated in Vista Service Pack 2. Another black-screen problem occurs because of a deadlock in the remote procedure call (RPC) component. It too has been addressed with a hotfix.
The most serious black-screen error I found for Vista systems involves a black screen and a system that stops responding. After you enter your user credentials in the logon dialog box, you see a black screen. You can still move the mouse pointer but cannot start applications. "After a while, the operating system stops responding," according to the Knowledge Base article. This issue occurs when an event log is corrupted; at startup. the Event Log service spins in an infinite loop, preventing you from logging on. I found reports of this issue on forums for several months this year before Microsoft finally released a hotfix in July of this year.
In each of these cases, the problem was relatively rare and difficult to diagnose. That's small comfort for anyone who had to deal with the issue. I have no doubt that a few similar issues are hanging around in Windows 7 waiting to be discovered and fixed.