W701 Lenovo SSD won't start, intermittent problem

Question

specs:
I think of W701 as the model number, but Lenovo considers it to be 4323CTO
It used to have a Lenovo 128 GB SSD as the C drive, with a 360 GB HD for the secondary drive. Now I've replaced the original SSD with a Samsung 512 GB SSD.
Running Windows 8 now, but it was doing the same on 7. It does seem to be a hardware problem.
This is an unusual problem. I posted here a couple of months ago. I have made a bit of progress since then, mostly in finding out what doesn't work.
It used to be an intermittent problem, but now it's frequent. It's happened since the computer was still on warranty, but it was so infrequent then that it wasn't likely to happen while tech was looking at the computer. It seemed pointless to complain or try to get it fixed. Lately it has been getting worse and worse.
It is 3 and a half years old and this has been the only serious problem, so I'm hoping for a way around it. When I press the power button to start it, it takes 2 or 3 seconds for the first visual to come on. It has the Thinkpad, Lenovo and Intel logos on it, and says: 'To interrupt normal startup, press the blue ThinkVantage button.'
That's as far as it gets. After that nothing happens, no drive activity at all and nothing I can do but shut it off. There is no response to the mouse or to pressing any key. Pressing the Thinkvantage button also does nothing. It would sometimes do this at least 50 times in a row.
What would get it going in those cases was:
1. leaving it for a few days or a week without touching it or
2. removing the SSD, replacing it with the HD (which would attempt to start but had no OS installed) and then switching back.
On one of these forums, someone described a problem that had some things in common with mine. It turned out his SSD was dying and when he replaced it, everything worked. I thought that might be it and replaced the drive. It worked for awhile but now it started with the same problem. (sigh)
I suppose it might be an intermittent connection between the SSD and the rest of the computer. Replacing that wiring harness would be my next guess but there might be other possibilities. I suppose any small electronic part involved in the start up process could be at fault.
Except for this problem it has mostly been a decent machine. It has a 17 inch, 16:10 screen which might not even be available now and I appreciate that size. I would like to get this restored.
tia

Answer 1

Thank you practical, that struck me as a great idea.
The little problem with it is getting an OS on the drive. I do have an image restore for Win 7, and after that it would take installing 8.1 again, so just a bit of work. But it seems clear to me now that the SSDs were not the problem. I basically agree with your comment:
"It sounds to me more likely, especially given the intermittent difficulties you have had in the past, that there might be an issue with the SATA electronics on the main board -- a tiny crack in a wiring trace, cable not fully seated in a socket (or perhaps contacts a little corroded) a flakey chip somewhere, etc."
I think the most likely possible solution now is to replace the motherboard. I saw someone else with a problem that had something in common with mine; he mentioned that he solved it by doing that. That would fit in with one of your comments. " there might be an issue with the SATA electronics on the main board."
So I started checking around at Lenovo.com and got the part number. I was able to talk to sales twice to confirm that it is the correct part number, and they transferred me to parts to find out about price and availability. Both times the parts person could not hear me, after having a normal conversation with sales. It seems like their phone system has some kind of problem with transfers. I called back 2 more times to let sales know about the problem, and got busy signals.
I had phone problems that I posted about in my T530i laptop problems topic. I had at least 3 calls that could not be completed by their system, and I'm starting to wonder about them getting anything fixed if they can't take care of that.
So I checked out the motherboard at http://www.sparepartswarehouse.com/IBM-Lenovo,Thinkpad,W701,4323000,Laptop,System-Boards.aspx They didn't have one in stock, and all the guy could tell me is that it would be more than $600 if they did get one in. I did appreciate even that much info. It was more than I had been able to get from the other supplier. I did see one on another site while searching that was over $1000 so I expect the $600 is low.
But this is getting seriously discouraging. This might change, but right now I feel like getting a Toshiba or something and just giving up on Lenovo. The prices of new laptops aren't that much now.
But thanks again for your comment. It jolted a bit of thinking, and most of the research I've mentioned in this post.