y510 never shows second 750m

[jewbaby 10]

I have been trying to find a solution to this problem everywhere..

I have a Lenovo Y510p, with the 750m and i bought seperately a GT750m5 for the ultrabay in around November of 2013. I thought it would be nice and easy to get both of the cards to function as SLI. If I go into device manager it shows 1 integrated, 1 750m, and nothing else under display drivers. I tried a bunch of random shit to get the 750m5 to work including upgrading my bios to 3.05..... Now when I put the gt750m5 and power on the computer it tells me an unauthorized product is in, to remove it and restart. I would like to either have an older version of the bios (please god someone have it) or find a fix to allow the gt750m5 to be installed, and to WORK as SLI like intended with the ultrabay. I am praying to the computer gods on this one. I broke down and called Lenovo support yesterday and since my computer ran out of warranty while i was deployed to kuwait they might make me pay for a fix. I did wait quite a long time to call them because I am a COMM guy and it hurts my pride to admit i need help.They assigned me a case number and said i would receive a call within the next 72 hours with a decision on if they will pay to fix my computer for me. I explained that it has NEVER worked as advertised and it is a known issue in the Lenovo world that the machines that werent SLI complete when they were sold dont ever work the right way. She said she didnt think it was and i assured her it is, at which point i was placed on an extensive hold and she came back with the case #. Has anybody else had any experience dealing with this and if so have you been able to get it working?

Thank you all for your time.

[octiceps 256]

Did you update vBIOS on the second GPU?

Laptops and netbooks :: IdeaPad Y Series laptops :: IdeaPad Y510p Notebook - Lenovo Support (US)

[gruebler 12]

To activate the second card in the y510p i right click on the destop and chose nvidia control panel. when nvidia control panel is open you see in the navigation bar on the left hand side "3D-Options"(or similar, my system is in german and it is called 3D-Einstellungen). when you click on it, the third and last item is SLI configuration. click it and choose the radio button "maximize 3D Performance."

I have attached a print screen: