Massive Hard Drive Speed inconsistencies! (200MB/Sec, then 60MB/Sec)

Hi Fellow Geekers,

I am having a little trouble with my hard drive speeds, be it the hard drive in my high end laptop, or my 3 different external USB hard drives (All different brands & sizes)

I recently purchased my brand new Acer Aspire V3-771G to upgrade from my February 2013 purchase of my Acer Aspire V3-571G, as that machine only boasted a GeForce 640M GPU, and this newer model boasts a nice GeForce 730M GPU.

Anyway, I have a 1000MB (1TB) Hard Drive in my laptop, I am unsure of the make and specs, but I also have 3 separate USB Hard Drives as follows:

WD USB 2.0 1 TB HDD
HP USB 3.0 2 TB HDD
Seagate Expansion 2 TB USB 3.0 HDD

At the moment I am moving data around, to sort it all out, and grab some of the files I want as well, etc, I have the Seagate Expansion connected into my USB 3.0 Port 1, and the HP Connected into USB 3.0 Port 2, and finally the Western Digital 1 TB Drive connected into the USB 2.0 Port 2 (Mouse connected to USB 2.0 Port 1)

And if I copy files from my Laptops internal hard drive, to say my new Seagate Expansion USB 3.0 Hard Drive I am lucky if I get a decent 40MB/Sec, that fluctuates between 40 and 50 MB/Sec.... And I just tried copying a few files from the Seagate Expansion USB 3.0 Hard Drive to my Laptops Internal Hard Drive, and at first I got a whopping 200 MB/Sec, which only lasted around 15 seconds, then it started to drop rapidly down to 40 odd MB/Sec for no reason.

When I am transferring data I am not doing any other tasks what so ever, I just leave the laptop be and wait until it is finished before I even touch the mouse again, so I am at a loss as to why I get such good speed transferring from the external to the internal at the beginning, then it suddenly drops dramatically and never goes back up again, and when I am transferring from the Internal HDD to the External USB 3.0 Hard Drive, I never break the 50MB/Sec mark, Surely I should be getting a lot faster data transfer speeds than this?

With my Western Digital USB 2.0 1TB Hard Drive I am lucky if I break the 20 MB/Sec transfer mark, that's from the Internal to the External WD Drive, same goes for the other way around.

I am using Windows 8 Professional, I have installed ALL the latest drivers (Including Intel Chipset INF) and I have checked Device Manager, and their is nothing showing any issues in their.

Does anyone have any idea how to increase my data speeds?

My System Specs are as follows:
Windows 8 Professional
UEFI Bios Version 2.21
Intel Corei7 3632QM Quad Core 2.2GHz CPU (With Turbo Boost up to 3.2GHz)
16 GB DDR3 Memory
4GB NVidia GeForce GT 730M GPU
17.3" Full HD LCD (1920x1080)
1000GB Hard Drive
Blu-Ray R/W Disc Drive
Acer Nplify 802.11a/g/n
Acer BT 4.0

- David aka The original Luthius