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The LED on my computer keeps gently blinking all the time. Is this a possibility of bad hard drive cable connection? Or is this just a case of a fragmented disk?

I haven't formatted my computer for half a year now. I am not sure how long this has been happening; I just noticed it now.

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Do you mean the hard drive activity light? Isn't it supposed to be blinking sporadically? – Shinrai May 2 '12 at 19:24
Dont know, i was not paying much attention to it before. – user6613 May 2 '12 at 19:35
I'm not going to assume what the Red light is. I'm going to request that you supply the make and model of your computer, as well as an exact description of the placement of this light (2nd from the left, the only red LED, etc). Without that information, everyone is only just guessing. Oh, and you've had the computer for over half a year. You sould have noticed the HD light blinking before this. – Bon Gart May 2 '12 at 20:14
up vote 1 down vote accepted

I am going to assume that the LED you are referring to is the HDD activity LED. You can tell by loading some big video then seeing if the light becomes drastically more accurate while the video is loading.

First off, HDD activity is not necessarily a bad thing, but being interested in maintaining your system is a good practice as if you become keen at it you can keep your system running smoothly and also see tell-tale signs of when hardware may fail.

1) If your OS is Windows XP and you haven't re-installed for years, do this first. Windows XP is terrible for keeping itself properly maintained, and after dealing with it for over 10 years, I have come to discover there are things so ingraned in it that cause "bit decay" the simplest method for maintenance is periodic re-installation.

2) If your OS is Windows Vista or higher (7) then your system should properly maintain itself, Windows 7 does it better than Vista though. Starting with Vista HDD Defrags always occur in the background every couple days or so. What would be causing excessive reads at this point would be applications or malware running processes you don't expect in the background, or possibly a failing HDD. If your HDD is failing it increases in activity as it has to re-read parts of data more and more.

3) Your system could be doing work that is actually reasonable. An example is if your Windows system is checking for updates, it will need to reference what is on the system before it can determine what updates you need. As a precaution best just update Windows completely.

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It is because Windows is polling the optical drive. Answered here.

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Go through basic troubleshooting steps. Scan for corrupted sectors you could use this tool to scan your disc from CD Ultimate Boot CD v5.1.1. Check the Hard Drive for fragmentation. Then it might be a problem try a different Hard Drive see if it's still doing the flashing.

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Windows does some maintenance tasks on its own. So just keep cool and enjoy perhaps a faster starting OS in the next days (yes, sometimes these actions take some time...)

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Oh okay, didnt know that. The blinking is actually very gentle, like one fast blink every 1-2 seconds. Thanks – user6613 May 2 '12 at 19:38

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