Hi Guys,
Not looking for help on this one, too late for that I'm afraid; just sharing the story with you to ease my frustration.
I had long planned to upgrade my laptop (Asus N56VM) to an SSD.  The plan was to get a deal on an SSD, clone it, install it in the main drive and put the old HDD into a caddy and use that to replace the DVD drive.  I waited until the last Black Friday came round and I was excited to see a Crucial 750GB SSD come up for just over £100 - a great deal and my project began!
I had checked out YouTube videos and everything looked very simple for my particular laptop and so it was.  I cloned the HDD using Acronis (came with the SSD) and inserted it into the laptop, everything seemed fine for about 2 or 3 minutes before I hit THE PROBLEM.  For no apparent reason everything stopped working; after checking the Task Manager I could see that Disk Usage had gone to 100% and just stayed there.  I could see no reason for this, but after trawling Google, I found potential solutions - there were a lot of possibilities.  To cut a long story short, I tried all sorts of solutions during which I had to reinstall HDD and SSD multiple times in order to try different things.  It was after one of these installations that I lost the motherboard!  I don't know whether it was a static discharge or something else, but the CPU cooked itself and I lost my laptop.  I had to pay £50 for the laptop repair company to diagnose that the machine could not be repaired and they helpfully told me that SSD installations are frequently problematic ("unless you have a very clean HDD").  It is not possible to get a new, replacement mobo.
I had been really happy with my laptop - it had 8GB (plenty for me), a 4-core i7 and 4 USB3 ports, it even looked good!  I now have a replacement Asus X556U and I was quite excited by the fact that it had the latest 7th gen i7.  Unfortunately it only has 1 USB3 and 1 USB2, but I bought a hub so I thought it wouldn't be a problem.
I find myself rather underwhelmed by the new laptop compared to the old.  It's considerably less well made and handsome, the i7 turns out to only be dual core and I think using a USB hub could be a problem after all - my audio interface doesn't like it so has to have it's own port, now there's only one left.  Finally, Sonar Platinum is giving me pops, clicks and audio dropouts - on a brand new machine!  I won't go into details on this, I will start a new thread if I need help.  I appreciate that I have to work through potential solutions first.  Just feeling very frustrated, sad and annoyed!

Your first problem, as I see it, was to "clone" the hard drive to the new SSD.  Cloning is a hit or miss operation and when you clone a drive the new drive gets everything on the old drive, even bad blocks and bad/corrupted data.  The best option is to "image" the old drive (backup) to some other media (drive) and then "restore" the image to the new drive.  Image does not copy bad blocks and corrupted data.  We had a lengthy discussion about this on one of the computer support forums and the conclusion from the "gurus" was it was best not to clone because of the iffy nature.
 
Whether this contributed even remotely to the motherboard problem???  The new SSD, itself, probably did not.  Having been inside the PC and the potential for static electricity discharge to cause problems is a major consideration. 
 
I got zapped on a new laptop with an i7 CPU.  It works OK with Sonar (for what I've used it for - a "tape recorder") but it is very slow.  You need to buy a high end performance laptop with an i7 to get close to a desktop in performance.  

Sometimes hardware finally dies when you start to mess with it. If it was an HP I wouldn't be surprised.

My thoughts on laptops are that they are disposable consumer items.  Not really meant to be user serviceable, full of proprietary components, and difficult to access and replace parts.  I would use one as a mobile DAW maybe, or as a secondary, but not as my main workstation.
 
I think that for the money you would spend on a high end laptop for audio, you could build a really sweet desktop DAW.  In a few years time you could keep up to date by just dropping in a future motherboard and CPU, and keep going with the same case, power supply, and drives.
 
One thing I have also noticed about the Intel Core CPU's for mobile, is that they are usually cut down 2 core versions due to heat and power consumption issues.  They also throttle down and go into economy mode.  And  often the BIOS won't even give you access to many options that you might see in a desktop mobo.

abacab
My thoughts on laptops are that they are disposable consumer items.  Not really meant to be user serviceable, full of proprietary components, and difficult to access and replace parts.  I would use one as a mobile DAW maybe, or as a secondary, but not as my main workstation.
 
I think that for the money you would spend on a high end laptop for audio, you could build a really sweet desktop DAW.  In a few years time you could keep up to date by just dropping in a future motherboard and CPU, and keep going with the same case, power supply, and drives.
 
One thing I have also noticed about the Intel Core CPU's for mobile, is that they are usually cut down 2 core versions due to heat and power consumption issues.  They also throttle down and go into economy mode.  And  often the BIOS won't even give you access to many options that you might see in a desktop mobo.

 The portability thing lasted about 2 weeks for me.  That was with an iPad.  I can do everything on it but I prefer to use it as a Kindle or Web streaming on the patio. I have an iTrack Solo, one of those IK things to use your guitar and various mini Midi controllers that I now use for a desktop.
 Most of my laptops are hand me downs and the modern day cell phone is just as powerful. They are HP and I call them craptops.
 One person referred them to as shiny new ornaments to show off at Starbucks.

abacab
My thoughts on laptops are that they are disposable consumer items.  Not really meant to be user serviceable, full of proprietary components, and difficult to access and replace parts.  I would use one as a mobile DAW maybe, or as a secondary, but not as my main workstation.
 

I do this. I record stuff on-the-go into GarageBand with my 2-input AudioBox, export WAV files and import them in SONAR on my desktop for processing.

I have a laptop that I can use for "on site" recordings.  But, its basically used like a multi track tape recorder.  Whatever is recorder is transferred to my desktop DAW for any processing. 
 
But, that doesn't negate the user's problems.  Replacing the hard drive with an SSD is a good idea.  The other part of the motherboard failing can be logged to "Murphy's Law" (anything that can fail will).

I have observed several SSDs which have failed at the very beginning, with different symptoms.
I had also describe behavior, the disk become ridiculously slow. Not sure which "a lot of possibility" you have found in the Internet, I know only one: send the disk back and get replacement.
 
Modern (at least last 15 years) HDDs have intelligent controllers, they are not exposing "bad blocks" to the user and try to handle them internally (relocating sectors). I mean "bad blocks" on the disk surface map are hard to observe, till that happens either SMART will beep every boot or the disk will be almost unreadable. I mean I have not managed to "clone" any disk with (real) unreadable blocks recently (while I could copy some files). Also modern cloning utilities rarely "blindly" copy sector by sector (till you use dd under Linux or utility which call it, f.e. for unrecognized file systems).
 
I had a HP notebook for 9 years. MB was dead once after first year (killed by the power supply...), was replaced for free. TFT backlit lamp has died 4 month ago, but 9 years of heavy every day use (most keys are "polished", touchpad's buttons ribbon void, etc.) is a reasonable lifetime for a notebook.
 
Static discharge is very imported when changing something inside computer as well as disconnecting the power (for notebooks disconnect power cord from computer, not only the cord from the power supply). Touching something "ground like", f.e. metal heating pipe, is normally sufficient. But if you periodically experience static discharges, correlated them to clothes or shoes (f.e. I currently wear "bad" shoes) and keep them away from you when working with electronics.

Hi Guys,
Thanks for all the interesting comments.  Just to clarify, I still have a working SSD, it was just the mobo that failed, but unfortunately it can't be replaced so the laptop is toast!  Interestingly, it was a 4-core i7 and I wonder whether cooling issues contributed to the problem.  The new one is only a 2 core, but seems quite speedy and it is 4 generations more recent - kaby lake vs ivy bridge, it seems to run a lot cooler.  
 
I never experienced a static discharge and I always disconnected and removed the battery before taking the cover off, but I presume there may have been a static discharge sufficient to kill the mobo without me knowing it.  Maybe just Murphy's Law as was said above.
 
I was very interested to hear about taking an image and restoring it onto the SSD rather than cloning it.  I'd never heard that before; just goes to show I should have consulted you guys first!  I had some very interesting advice from the chap at the laptop repair shop regarding the new laptop:- don't install the SSD until the warranty runs out.  The warranty is really valuable and totally void if you've done any upgrades.  He also said to be somewhat cautious of putting the HDD in a caddy and into the optical drawer, that it doesn't cause cooling problems.
 
I certainly get your comments about having a desktop machine rather than a laptop for DAW work.  However, I am not a power user by any stretch of the imagination, I do need the laptop for other things and it does need to be portable.  Maybe one day we'll buy a house with lots of rooms and I can have a studio room to myself and then have the desktop option ... haha, maybe!  You have made me feel quite defensive about laptops though and I feel I should point out that my machine is no slouch and way above the minimum spec.  I did have problems with pops and audio dropouts to begin with but since then I've stopped plugging the audio interface into the USB hub and worked my way through Cakewalk's PC Optimisation Guide.  Specifically, disabled wifi and bluetooth devices, also USB hub power management option (I only knew about the first of those previously).  Things are much better now but time will tell!  Does anyone know if it's possible to have a macro to switch these things on and off with a single click, rather than doing them all manually?
 
Since my first post, I have discovered that I have another USB port and I didn't realise it!  It's a USB 3.1 Type-C and apparently it's a speedy little beast.  I didn't notice it before because it has a different connector, but it could be very useful in future; I understand that it will transfer more than 1GB per second!  That will get external backups done in a hurry and I can also think about maybe using it for sample libraries too.
 
Anyway, for the time being I am feeling a lot better and I have gone through the process of removing unnecessary junk from the new laptop so am feeling like I have quite a streamlined machine now.  Thanks for all the comments guys!

SGodfrey
Thanks for all the interesting comments.  Just to clarify, I still have a working SSD, it was just the mobo that failed,

You have mentioned that problems started when you have inserted SSD, the disk use was 100% and the system has stopped working...
If you have not replaced this SSD, I recommend to deeply check it, may be with some old computer, may be even in (cheap) external enclosure. Check at least SMART health and disk speed, f.e. with HD Tune.