Q: 2010 mbp checkered screen

I have a 15" mid 2010 that I had installed an SSD drive in and installed Mavericks. After a month or so it has developed a problem with the screen.

I was seeing a checkerboard pattern especially after starting the browser. To see if it was a problem with Mavericks I reinstalled my original hdd, (with snow leopard installed). I have done a bit of searching and I thought it may be an issue with the graphics card, so I ran a "D"iagnostic, but reported that it could find no fault with the system.

I have now installed gfxCardStatus and set it to intel only and this seems to have had some effect on the issue, I get a partial checkerboard over the screen at startup, but once the apps are running it clears up and the screen looks normal. Im guessing that I have become a casualty of a problem with the graphics cards in these computers and am left with a functioning mbp with only intel graphics as an option.

As far as I have read the logic board might need replaced, but in searching I thought I found an article that said that there was an extended support for this issue. I can't find this page again, so am gong to contact apple support directly, but unfortunately as my original support is over, there is a £25 fee for any help they can offer.

I thought I would ask here first, to check that I have diagnosed the fault correctly and if it is even worth fixing the fault at this point, (or if i can get it fixed for free!). I have a very well looked after MBP with a healthy battery that can be used for the time being for everyday tasks, but I guess is useless for heavy lifting.

Thanks for any help or suggestions you can give.

(If this is disjointed and makes little sense i had 3 people talking to me while I was trying to type. Every time I put my head down they start, so I apologies.)