It can be a bit unusual for a 75w card to require a 1x6-pin connection, but some do.  If that is the case with yours, it would need to be connected if you wanted to use it.  Does gtx 1050 ti require pcie cable? 
I bought a 1050 ti msi but it doesn't work although it should work without an extra connection because it only has 75 watts but when I try to turn it on nothing happens. I've had it for about 1 month and I just leave it in the mainboard though it still doesn't work not seen a single reaction from it not even the fans are turning i'm going to buy a new psu but wanted to ask if you can get the card to run without a psu upgrade and otherwise i wanted to upgrade to an rx 6600 i.e. that The question is whether you can do something there without buying a new cable because if I have a new PSU the cable doesn't bring me anything, thanks in advance.
msi 1050 ti in 7020 mt optiplex