Very damaged screw, can't unscrew it

[razvy_aga]

Hello guys, last year my hdd failed so i went with my laptop at the shop so i can get it fixed with warranty. All good, but now i want to upgrade to an ssd (since the hdd is 5400rpm). When i got back my laptop from the warranty, i didn't checked my screws (who does that) because it was at a "specialized" repair center. Now when i unscrewed almost all of my screws from the bottom, i saw that 2 of them got their heads broken, so my little cross screwdrives is useless. One is holding the cd rom and another one is the second from the bottom so there is nothing there to damage. Their heads are really broken, like you can't even see the cross, just the round shaped head and a hole inside.
I searched on youtube and saw some dudes with a hand drill and with a 2.5mm screw bit and using it on the broken screws. Can i use this method or do you guys got any other method?
How can i remove them?

[CherylG]

If the screws aren't super tightened you may be able to stretch a rubber band over the tip of your screwdriver and get enough grip to loosen the screw.

[razvy_aga]

I will try. But as a last resort can i use the method with the drill?

[Paul110]

You could use a reverse cut drill bit with a drill on its reverse setting (sometimes this alone will loosen the screw) to drill a small hole in the screw and then use whats called a screw extractor, again on a reverse drill direction and this should hopefully bite into the hole you've drilled and remove it. My experiance with such processes has not been good and that was on a normal sized screw, not some tiny laptop screw. If you can't find the reverse drill bits you can use a normal forward directional drill bit. Good luck finding all those tools in such small sizes though! Don't press hard when drilling with small drill bits, they snap VERY easily. 

Persoanlly with something like that I'd take it back to the place that did the warranty work and explain it all to them and ask them to sort it out since it is obviously their fault. Don't take no for an answer. Depending on where in the world you live you may have rights to having the screws removed free of charge.