HDD light blinking for no apparent reason

[rdl]

The computer is 8 years old and I think it has always done it. It blinks once per second even if there is no drive activity. I have a quartz wall clock close to the computer and the ticks are, as far as I can tell, exactly in sync with the blinks. Pretty weird huh?

[Siwastaja]

Most obviously, the operating system is reading or writing something once a second. Could be writing a log file of some service, for example.

[rdl]

As far as I can tell, the blinking still occurs even when there is no reading or writing of files. It's very regular and steady, not random at all. Also, is not as bright as real read/write activity. Seems like maybe something in the hardware is causing it.

[rdl]

Hmm, that could be what it is. Everything is SATA, but there is a DVD drive. I suppose it could be Windows checking every second if a disc has been inserted.

Computers can certainly be weird. I have a computer that would blink the HDD light with a PCI wireless card installed. I switched to a USB WiFi and the blinking stopped.

[MrMobodies]

I came across an issue like this back from about 2010. On some Windows Vista and Windows 7 installations (not all of them) the HDD light was blking all the time idle, even with many services disabled, updates, search indexers, superfetch, etc. Very small read and writes but I read somewhere it was to do with this:

NtfsDisableLastAccessUpdate

https://winaero.com/blog/disable-ntfs-last-access-time-updates-in-windows-10/
https://superuser.com/questions/200126/are-there-any-negative-effects-of-disabling-the-last-access-timestamp

It seemed to have stopped when disabled.

I traced the reading/writing to svchost.exe in process monitor to a module that I can't remember to do with the ntfs file system.

I once tested a disc image with this problem on a different board and it didn't blink much all but the small read and writes were still showing in process monitor even after I installed the drivers. The only thing different was the chipset and sata/ide controller. I believe it may have be down caching policies on certain hard drive controllers/drivers. Then I found it was doing it on my stuff too but the led's didn't blink much.

[T3sl4co1l]

Heh, seems like I've had that here and there, all the way since Win98SE!  Don't even remember what the answer was back then...  Don't think I ever had it on Win7, and indeed the linked thread seems to show why.

Tim

[james_s]

I remember that happening when there was an optical drive that the OS was constantly checking to see if a disk was in it. Does the HDD light come on when the optical drive is accessed?

[Twoflower]

Maybe it's worth to see if the Sysinternals Suite, especially the DiskMon, from Microsoft shed some light on the unexpected accesses to the HDD. Be careful, these tools are powerful tools. So be warned.

[rdl]

I've been watching with Process Monitor and Resource Monitor. It's not often that Windows stops hitting the drives, but every now and then it pauses long enough to see that the steady one blink per second continues even when no drives are being accessed. I'm almost 100% certain it's Windows pinging the DVD drive, I just haven't had a chance to test it out.

[alsetalokin4017]

This computer here does that too. Maybe just a bit slower than 1 per second. I first noticed it after installing a new SATA 500GB Western Digital hard drive some years ago, but I can't swear to whether or not it did it before that. Tried to run down the reason for it, and never did figure it out. It seems to have no consequence, so I just consider it a "heartbeat". In fact at this point I would worry if it suddenly _didn't_ do it.

Oh... and I run Ubuntu Linux, never have had a Windows system on this box or any of its HDDs.   

[Halcyon]

It's perfectly normal. Even if your machine is seemingly doing nothing, there are still reads/writes happening in the background. You can use a tool such as Process Monitor to see exactly what is being written to or read from disk.

[Chris_Walch]

For Windows there are more handy tools by NirSoft:


https://www.nirsoft.net/utils/app_read_write_counter.html
https://www.nirsoft.net/utils/file_activity_watch.html

[rdl]

Well, as I said, I have used software utilities to verify that there are no disk reads/writes going on when only the one blink per second blinking is seen. It's a little difficult because Windows truly abuses the C drive, but there are times when it settles down long enough. Also, every drive in the computer has its own activity indicator light and none of them correlate with this steady one blink per second.

I'm almost certain it's Windows polling the DVD drive. I should have checked this by now, but I keep forgetting. I'll make it a point to test this the next time the machine is not in use.

I did confirm that the HDD light does appear to blink in sync with the light on the DVD drive when it's in use.

[Twoflower]

Short question: Is that HDD and DVD on a parallel IDE? If that's the case: Check if the jumpers (primary/secondary drive) are correct.

[Halcyon]

I did confirm that the HDD light does appear to blink in sync with the light on the DVD drive when it's in use.

As it should. On most machines, the "hard disk" indicator shows traffic on the interface, not necessarily just the hard disk. Yes, it could just be checking the optical drive for a disc (I'm not totally sure how that works), but I would have thought that the drive sent a signal to the OS, not the other way around. I could be mistaken though.

Short question: Is that HDD and DVD on a parallel IDE? If that's the case: Check if the jumpers (primary/secondary drive) are correct.

Which century are you living in? 

[Twoflower]

DVD drives used to be P-ATA some time longer compared to HDDs. But probably you're right as the PC from rdl is from 2012 it might be a bit too late for a P-ATA interface but still possible.

But I know several people cary over several generations of HDDs from older PCs. In some cases it was a so absurd having several dives from 20GByte+ down to 500MByte . And complaining that the mainboards don't come with enough IDE connections...

Halcyon is probably right. The HDD-Led will lit if any drive will be accessed. Not sure about if in the 'old days' the drives itself has a signal that the main-board OR-ed for the LED or if the chipset/IDE-Controller generated that signal. At least some HDDs had an LED itself. Today I'm not sure as it get's more complicated with the M.2 (PCIe or SATA) and SATA drives; so it could be the chipset or the driver. I'm not sure but think it is on also during boot (I never connect the HDD-LED anymore) so I tend to thing the Chipset is doing that as no driver/OS can be involved that early.

[rdl]

Two of the drives in the computer are in an Icy Dock front panel SATA "hot swap" bay. Both have individual power/blinky lights (lights green, blinks orange with activity), so apparently drives still have the ability to blink an LED if one is hooked up. I've noticed different drives will light the power LED at different brightness levels, so I'm pretty sure it's not the Icy Dock doing the lights.


I think this is the one I have.

https://www.newegg.com/icy-dock-mb992sk-b/p/N82E16817994148

[Monkeh]

Two of the drives in the computer are in an Icy Dock front panel SATA "hot swap" bay. Both have individual power/blinky lights (lights green, blinks orange with activity), so apparently drives still have the ability to blink an LED if one is hooked up. I've noticed different drives will light the power LED at different brightness levels, so I'm pretty sure it's not the Icy Dock doing the lights.


I think this is the one I have.

https://www.newegg.com/icy-dock-mb992sk-b/p/N82E16817994148

There is absolutely nothing on the drive to control the power LED. Activity is presumably by pin 11 on the power connector being pulled low (a fairly recent addition).

[rdl]

As I remember, I noticed the brightness difference of the power LED when I swapped a Crucial in place of a Kingston on the same tray. It's been several years since, so I could easily be wrong. If I can find the box with the Icy Dock stuff, and remember to do it, I might try swapping the two drives again. A quick look just now didn't turn the box up, so I may have to clean out a big walk-in closet that's absolutely stuffed. About the pin 11 thing being recent, I have SSDs 6 years old that blink the activity light in the dock. I might still have one from 2012.

[rdl]

No luck so far finding the Icy Dock stuff, however I was able to determine that the steady blinking is definitely due to the DVD drive. 

[Mr. Scram]

I've seen many Windows computers do this. Not sure about other OSs. It's completely normal.

[mikerj]

NtfsDisableLastAccessUpdate

https://winaero.com/blog/disable-ntfs-last-access-time-updates-in-windows-10/
https://superuser.com/questions/200126/are-there-any-negative-effects-of-disabling-the-last-access-timestamp

Note that querying the current value via "fsutil behavior query DisableLastAccess" gives confusing information:

Code: [Select]

C:\Windows\System32>fsutil behavior query DisableLastAccess
DisableLastAccess = 3  (System Managed, Enabled)

A value of 3 = System Managed, Last Access Updates Disabled, so querying it tells you that "Last Access Updates Disabled" is enabled 

[PlainName]

Could it be SMART monitoring, or other non-data interrogation?

[Syntax Error]

I too would suspect the HDD Firmware, the BIOS or some other dumb proprietory feature from the manfacturer's code bloat payload. But just maybe...

This reminded me of an apocryphal story about a guy who once purchased a fabulous top-of-the-range video recorder. Despite having a feature packed specification, the display had a red light that, for a reason unexplained in the owners manual, just kept on blinking. But every time he turned the video off, the lamp just kept on blinking. So he unplugged from the wall, and the lamp just kept on blinking. Even after a week without any power, the lamp was still blinking. So he took the video to a repair shop who could find no problem, except for a mysterious and unspecified lamp that just kept on blinking. And for weeks and weeks, with no power, the lamp kept blinking. And blinking. And blinking... So the guy prized open the lid to see if he could fix it himself. He started removing random parts; some wires, a circuit board, some more wires, a bit that looked kind of important, and lots of screws. But that lamp just kept on blinking. Infuriated, he threw the video to the floor and began smashing it with a lump hammer. And the red lamp just kept on... mocking him! So he poured gasoline over the pulvarised chasis and set fire... burning his house to ground. And in the smouldering ash of his home, beside his charred skeleton, that darn red lamp, is still blinking.

@rdl You've got yourself a deamon lamp. Just ignore it