I have a system with Windows XP and Vista dual booted on it. I have 4gb of ram, an Athlon 64 X2 processor, on it, to run Vista. I have also not done any overclocking on this machine. But the problem is that when ever the system stays at IDLE, then the hard drive light is continuously flashing and I can even hear it reading the hdd. I have partitioned this hard drive into half size and there are also plenty of space available. Can anyone let me know what should i do to fix this issue.
I think that the hard drive is running continuously since Vista might be indexing it. There is no need to worry because it will eventually be stopped after some time or days, calculating about how many files are there in your system. Due to faster search capabilites, the scenario might be happening and at that time you will notice a lot of activity in the hard drive. You can try to turn of the superfetch and indexing from the hard drive and see if that makes any difference in your computer. But note hat if you turn off prefetch then the system might slow down a bit. So to get enough performance, you can turn it back again, as per your choice.
You can try to use the Performance and Reliability Monitor in Adminstrative Tools if you want to get some information related to the hard drive activity, like whats going on with it. It will give you useful information and will suggest you to take a course which might be helpful. You could either get to know if the system is spending too much excessive time writing to the page file or something other in the report. It normally depends upon what kind of program you are running and how memory intensive the same program is.
You can try to close all programs and then run Perfmon, after that click on Disk and then on disk write. Here you will see disk write drop off to nothing incase if your system sits idle for long time. If that is not the case then check what could be causing the disk IO. If you turn off Superfetch and indexing on the drive that you are using then it will kill a lots of disk IO that wont effect the system performance. The hard drive light can let you know about more than just fixed disk activity. If IO light keeps blinking in your case for about once a second after the disk write activity stops then there might be no disk activity. This issue could be because of the Sata/Ide chipset IO polling that is related to the CD/DVD drive and you can disconnect the same connection if needed and check if that reduces IO activity.
There are many things that run in the background with Windows Vista. It is not that you will get to know about the disk light does not flash occasionally due to indexing of drives or defragments of drives. There are also alot of things like relocation that is mostly used to find stuffs to the fastest part of the drive, buliding lists of most used apps and so on. So, due to all this things, flashing hard drive lights are normal in Vista and one can expect the same to happen every now and then.