Hi.. i recently added an 500gig seagate sata drive to the existing 250gig sata one.. off late.., the HDD led on the front of my cpu (that normally lights up bright when there is hard disk activity) glows very dimly as a bulb would when there is a low voltage.. and at times it is bright.. when there is no hdd activity it is still burning dimly continuously.. is this a symptom of poor connections or a failing psu or a failing bulb or a faulty connector?

I guess it would be useful if i mention this information.
I have 4 power connectors(the 2 black,1yellow,1red design) emerging out from the psu..however, there are not 4 dedicated power output connectors from the psu. its LIKE a pair of connectors PUT together and two such pairs thus making it 4. From the head of one connector, 4 wires branch outwards to the other connector thus making a pair.. mean to say that, not all the 4 connectors emerge directly from the psu.

My initial configuration before buying the new hdd where all was fine was the first pair of connectors were connected to the two optical drives.(one cd-rom and one dvd-rw drive)Among the second pair, one went to the 250gb hdd and the other one to the additional fan on the side of the cabinet (sometimes this one would be connected to a splitter in case i wanted to activate both the fans that were present..)

After the new hdd was installed, i was PLAYING around with the connectors a lot of interchanging plugging and unplugging repeatedly atleast a dozen no. of times since the hdd would either not boot up or hang or not respond once booted up.. Not sure if this interchanging of the connectors caused the problem with some connectors,i could see that the hdd's(either of those) would boot when connected to a particular connector and not boot when connected to the other.

By the way, guess all the connectors can be switched between the optical drives,hdd's,fan as they all consume the same voltage.. am i right?

Due to the above behaviour, i ruled out one of the connectors to be faulty. But then again today, one more of the connectors failed leaving me with only two connectors for the 3 devices available..I would also need a confirmation from the experts here whether this behaviour of the hdd not being detected actually means the connector has failed? however, when i connect these 'supposedly' failed power connectors to the optical drives, they are being detected although i am not sure whether they would cause a problem when reading/writing data.

Let me also tell when i saw this dim let LED problem for the first time. As i stated earlier, one pair of connectors were shared between both the optical drives. In this setup, i disconnected one of the optical drives, and connected a splitter cable that i bought to the other connector. The two outputs of this splitter cable were shared among the 2 sata hard drives.. and this was the first time i saw this dim lit problem..

Not sure what could be CAUSING this.. kindly assist!
Thank you