During the past two months I have built two new Windows-based systems using the Seagate Barracuda 500GB 7200.11 hard drive, model ST3500320AS, in a non-RAID config. On both systems, using different motherboards and other dissimilar hardware, the disk activity light pulses at a rate of approximately once per second during system inactivity with Windows XP or Vista booted from either a DVD/CD to the install/repair prompt or full startup from the hard drive. The pulsing continues to take place even after dismounting the hard drive volumes when boot up took place using a DVD/CD. SATA AHCI or IDE modes don't matter. In comparison, booting up on a PuppyLinux CD and the disk activity light is nearly perfectly quiet during inactivity even with the hard drive volumes mounted. Otherwise, it seems to have no effect on hard drive performance. In fact, Vista gives the hard disk performance a 5.9 on both systems. The motherboards are Gigabyte P35C-DS3R and GA-78GM-S2H with Antec 900 and Apevia X-QPACK2 cases, respectively.

This is leading me to think that this is a Windows driver issue for this fairly recently released hard drive. Otherwise, I find it hard to believe that I am the only one experiencing this. Thoughts, feedback? Thanks.

This is normal for both XP and Vista, if you look at the program manager you will see that lsass hits the cpu and the hard drives blink every second. This has nothing to do with any issues with hardware or other software. This is just part of windows after win2k.

-------WARNING THE FOLLOWING IS TINFOIL HAT PARANOIA----------

I think it's MS spying on us. LOL

Having observed the disk activity light on countless XP machines over the years, this is my first time observing a constant "polling" type disk access. Secondly, the resource monitor in Vista does not or is incapable of showing the lsass service as such a frequent task to the CPU or hard disk. Based on your understanding, am I to conclude that the disk activity display electronics on these motherboards does a much better job than previous motherboards?

What I can tell you is that from it's release (I started using XP Pro less than a month after it's release) I put XP Pro on my Abit dual celeron BP6 system. At the time I was running Win NT4 on it. With a dual boot setup I right away noticed that this behavior was taking place. By todays standards the BP6 is a relic. With the speed of todays systems it nearly impossible to see this.

It's not LSASS.EXE it's self that is dong this but another component of Windows XP/Vista making a procedural call through it.
If I recall correctly it has something to do with drive indexing. Nun the less it's part of the windows system architecture post Win2K.

Somewhere in the MS windows knowledge base is a description of the LSASS.exe and calls to it.

I would think that this consistent pulsing at exacting intervals (i.e. 1/sec) during "idle time" is something many XP users would have recounted often over the years. Sorry, but I just don't see that as being the case. I just took a look at my son's Northwood P4 running XP Pro and the hard disk activity light is as quiet as the eye of a Cat 5 hurricane.

Cool, happy to hear, I can only give you what I have experienced.
As I really do not have anything else to impart to you, I bid you adieu.
Good luck in your quest.
From here on may Google be your guide.

I suspect the activity is due to the CD/DVD autorun feature being enabled. Disable the autorun feature or disconnect the CD/DVD and check if the activity stops.

I thought the same and disconnected the other drives, but to no avail. Indexing, superfetch, readyboost, system restore, etc have been disabled. To reiterate, the pulsing/polling occurs even after unmounting the volumes on the Seagate when booting up from the DVD/CD. BTW, the first system is Core 2 Duo Conroe based and the second is Athlon 64 X2 Windsor based.

You know, I have the same drive and while I cannot comment on the HD activity light (apparently I missed a connection when hooking up the case and mobo), it always sounds like there is some minor drive activity even when the PC is idle. This is on windows XP on a gigabyte p35 ds3l, similar to one of your setups. The board was just installed last week and I never noticed this activity using my previous board, an asrock 939-dualSata2. I'll boot into linux when I get home from work to see if the same thing is happening.

Grab a copy of FileMon.

You will be hard pressed to find a full one second interval where something is not reading something from the file system. This holds true in most cases.

I appreciate your point about OS sophistication. However, the exacting polling/pulsing occurs even when the volumes on the Seagate are not mounted. I confirmed this by booting up using a Vista DVD and XP CD and unmounting the file system volumes through the command interface. To reiterate, this is not an issue when booting up with a PuppyLinux CD with the volumes are mounted.

i also have this 500gb hard drive and the 750gb seagate 7200.11 for about 8 months and i havent noticed problems like this. it only gets loud when i first login to windows and all my startup programs are turning on. mobo i am using is msi k9a2 platinum. ahci mode, windows xp and Ubuntu linux both stay quiet.

A quick search shows this behavior has been reported for years. Here is a thread from 2006 that goes through some possibilities including CD-filtering.

Turning off Desktop CD recording (Drive Properties > Recording tab > "Enable CD recording on this drive" checkbox) worked for this guy.

http://techreport.com/forums/viewtopic.php?t=42726

I just bought the same Seagate drive with my new setup and have been experiencing the exact same issues Rob has described. There is no way this was happening with my previous system or any system I have run across. Every second or so - a few clicks and HD light flickers. I think I also hear a very faint humming sound when it's not clicking. No performance loss from what I can tell.

Some info:
Intel Core 2 Duo E8400
Intel DG35EC MB
2GB OCZ DDR2
Seagate 7200.11 500GB ST3500320AS Firmware SD15
Windows XP SP3
Office 2007 Enterprise Ed.

I have tried IDE, AHCI, indexing off, write caching off, autoplay off, system restore off, unplugging my DVD drive, changing different BIOS settings -- all unsuccessful.

Anybody figured this one out yet? -- New firmware for drive? -- New windows driver?