I just built a new PC ~2 weeks ago with the following:

• Antec Sonata III 500 Black 0.8mm cold rolled steel ATX Mid Tower Computer Case 500W Power Supply - Retail
• Western Digital Caviar GP WD5000AACS 500GB 5400 to 7200 RPM SATA 3.0Gb/s Hard Drive - OEM
• CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory Model TWIN2X2048-6400 - Retail
• Intel Core 2 Duo E8400 Wolfdale 3.0GHz LGA 775 65W Dual-Core Processor Model BX80570E8400 - Retail
• ASUS P5QL-E LGA 775 Intel P43 ATX Intel Motherboard - Retail
• XFX PVT88SFDD4 GeForce 8800GS XXX 384MB 192-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Retail

I'm also using an older single layer NEC DVD burner and a Toshiba DVDROM drive.

My problem is that if the PC is on for more than a few hours, it won't shut down. I have Windows XP Pro and it shuts down. The monitor goes black but the PC itself is still running.

Searches on the net point to a possible issue with ACPI. I only found a setting in the bios for ACPM (not sure if that is the same thing.) ACPM 2.0 support was disable but I enabled it. Problem still exists.

There are no APM tabs in Control Panel for me to configure.

I thought it might be an Intel chipset issue. I downloaded the auto installer but can't tell if it installed anything. It decompresses the files to a folder but it never goes and runs thru the install.

I have Microsoft's HIVE cleanup util/service running. I don't think this is an issue becuase XP does actually shut down.

I have an external thermaltake enclosure with a WD 160 gig drive connected via USB 2.0, an HP P1005 laser connected. Nothing else other than some open ended USB cables for my mp3 player and camera.

Sooo.....any ideas what the cause is? Other than this, the PC is running great.

Are you sure that pc is still running or it your psu fan?
some psu cool down when you turn off your pc.

hey, i've got even better: had the same problem. you shut down XP your screen goes black but only your casefans and (if it work also) your psu fan still turns.
i had only that problem when i was gaming and than shut down the pc imediatly. but if i was only surfing, the pc did normal. now with service pack 3 i haven't YET get the problem.

so my main question to you is: did you warm up your pc by some heavy applications?

did you game, and shut down after it within the same minute?

Well, yesterday, I did play Doom 3 for a few hours. Another time I was editing a video but the PC barely broke a sweat (per Task Manager). The first time, it was general IE browsing.

I'm also running XP Pro with sp3 and all updates applied after that. Video drivers are up to date as well.

Sorry, that should've read "Antec"

If you hold down the power button for more than 4 seconds, does the PC shutdown?

i can't expect that i know every english word. do you know my language? i guess not

i think the most important thing is, that he has got my point!

ps i'm not dutch, i'm belgian (we don't like the dutchmen)

i have an asus p5ld2 old model rev 1.0, i started to have this problems only this year. i have it for almost 3 years. maybe it is an asus problem. dispite, i like my pc, never had problems with it...

In Windows, what should the power button do when you press it? Stand by, Shut down, Ask me what to do?

Does the PC power down when pressing the power button if it hasn't been on for too long? If so, what are your APM settings in the BIOS?

I found another thread where users had trouble with the dvd burner/rom drives attached to the master/slave connections on the IDE. My only IDE drives are my burner and rom drives. They are both configured to cable select. I know you're not supposed to have an optical drive listed as the master with an HD as a slave (can't recall the reason why). Do you think this could be the problem?

I'm thinking of ordering a SATA-based dvd dl burner. I was holding off on it but if the above is true, I'll place the order today.

The only setting I changed was the ACPI 2.0 support to enabled. I changed it after I had the OS installed with all of my apps when the machine would not shut down automatically.

What is HAL and how do I check to see if it's currently in use.

I disabled both ACPI 2.0 and APIC support. The PC wouldn't even reboot. I renabled it and all booted up OK.

It failed to boot. BIOS startup screens appeared and then screen went black.

OK, it looks like it was a defect with the JMicron IDE/SATA drivers. The driver had an issue where the PC couldn't be shutdown if an ODD (optical disk drive?) was connected. I have both of my dvd drives hooked to the IDE controller.

ftp://driver.jmicron.com.tw/jmb36x/Win2k_xp_Vista/

So far so good. I've only had to shut down twice since installing the drivers late last night. I'll see how it goes.

A service, e.g., wi-fi, could prevent the computer from shutting down. If you boot in safe mode, does it shut down properly? If so, then try to stop a few services and then shutdown to see if it works. It's a tedious process, but it should allow you to determine what's causing the issue.

You should read [url=http://askthegeek.kennyhart.com/2007/08/computer-won-shut-down-try-this.html][/url] as well as the Microsoft article they are referring to.

Shutting it down by holding the power button for more than 4 seconds will not harm it, but always wait for long enough to make sure that all tasks have stopped before doing it. Otherwise you could lose data.

If it didn't recognize the video card, it would use the standard VGA drivers. That wouldn't prevent it from shutting down. On the other hand, you could test with a different video card or even an old PCI card.

What's your BIOS version? Did you install the Intel drivers for that chipset? What about other drivers?

I have an Asus P5WD-2 deluxe and a P6T-SE with diferent videocards, they both won't shut down after the SP3 update.