Could a lack of power be the reason that my HD is lagging, clicking, and freezing?

Question

I replaced my HD with a Seagate 500 GB 7200 rpm hard drive. It turned out to perform worse than my previous hard drive. It lags, clicks, and has frozen twice in one day. I emailed Seagate, and they suggested that if the computer isn't getting enough power, then the HD could encounter these problems. I had not thought of this before, but could this be the case?

Answer 1

The other thing to do may be to add more RAM capacity, of reliable and reputable quality specific part number series and matching pairs to assure they are able to work correctly in support of the data paths in the iMac 27"
Depending on the options you chose or what was offered when you bought your iMac, the device can support a higher ceiling and this helps certain applications run better, and also the OS X system likes a lot of RAM.
According to what you say your iMac 27" model is (late 2013) the RAM amount & specs are as follows:
Built-in Memory
None
Maximum Memory
32 GB
Memory Slots
4 - 204-pin PC3-12800 (1600 MHz) DDR3 SO-DIMM
{according to http://mactracker.ca for Late-2013 iMac 27" model}
•iMac: How to remove or install memory:
http://support.apple.com/kb/HT1423
(see if mid-2013 item compares to your model)
If your unit shipped with more than 16GB it may not need more, at least for awhile. I see this Late-2013 model is not listed in the Support article on how to remove or install memory in iMacs, the model is like Mid-2013 and so it should be user-accessible. If you choose to upgrade the RAM ask Apple about it. A fair deal on upgrade could be found through online resellers with Apple knowledge such as OWC 'other world computing' http://eshop.macsales.com/shop/memory/iMac/2012_27/DDR3L
Hopefully this helps...
Good luck & happy computing!