I'd take the motherboard out of the case and try to run it on a table with only the old CPU, one stick of RAM, the video card, and a keyboard and nothing else connected just to be sure it's really damaged. But if the minimum possible configuration doesn't work then you probably damaged it. When you're installing or uninstalling a heatsink with a screwdriver it's a good idea to put a small piece of cardboard next to the CPU socket in case the screwdriver slips off. I guess it's a bit late for that advice but now you know what to do next time. Newer motherboards tend to have a little protection strip in the screwdriver area but I still use the cardboard protecter trick because the protection strips are awfully thin.
There's a chance you might be able to recover the motherboard if you've shorted some of the traces together rather than broken them. When you hit a PC board with a screwdriver you often chip the solder mask (the colored stuff which covers most of the outside of the circuit board) and short a few traces together. If that's what happened then you might be able to isolate the traces again by taking a razor blade or XActo #11 blade (scalpel) and cutting back and forth between and parallel to the damaged traces. That will remove any conductive bridge you've made between the traces if you dig it out just right. But if you cut too deeply you can damage stuff underneath. You have to be careful when doing it. Reworking motherboards isn't easy even when you've got the correct tools. Whether that works or not depends on what kind of damage you've done but if the motherboard's a goner anyway then you've got nothing to lose by trying. I'd definitely make sure the motherboard is dead by trying the "minimum possible configuration drill" before putting your motherboard under the knife.
There's a chance you might be able to recover the motherboard if you've shorted some of the traces together rather than broken them. When you hit a PC board with a screwdriver you often chip the solder mask (the colored stuff which covers most of the outside of the circuit board) and short a few traces together. If that's what happened then you might be able to isolate the traces again by taking a razor blade or XActo #11 blade (scalpel) and cutting back and forth between and parallel to the damaged traces. That will remove any conductive bridge you've made between the traces if you dig it out just right. But if you cut too deeply you can damage stuff underneath. You have to be careful when doing it. Reworking motherboards isn't easy even when you've got the correct tools. Whether that works or not depends on what kind of damage you've done but if the motherboard's a goner anyway then you've got nothing to lose by trying. I'd definitely make sure the motherboard is dead by trying the "minimum possible configuration drill" before putting your motherboard under the knife.