Can I just toss my GPU in the trash?

I disassembled my rig to clear out the dust (which I do every few weeks)
After putting everything back together, I powered it up only to find the GPU fans spinning like crazy. In my negligence, I realized I hadn't actually plugged in the power connector properly. I shut it down immediately and connected the cable, but now my frame rate has plummeted from 70 to 30 in one particular game.
The fan is spinning at normal speeds, yet the card is overheating excessively.
Is this thing a lost cause?
For context, I'm running an HD4870.

Gregory Hayes87 said:I took my PC apart to clean out the dust (which I do every few weeks)
put everything back together, hit the power button, and the GPU started spinning like crazy. I realized I hadn't plugged in the power connector properly. I shut it down immediately and fixed the connection, but now my FPS dropped from 70 down to 30 in one of my games.
The fan spins fine, but it's overheating like crazy.
Is it dead?
It's an HD4870, if that matters.

Pull the card, take off the heatsink, and apply fresh thermal paste. If you haven't done this before, just take it to a pro.

I can't get this refrigerator out; I'd need superhuman strength just to loosen these damn four screws.

Don't even bother turning it on until you swap out that thermal paste and seat the cooler properly, otherwise, you’re going to fry it. You might have shifted the heatsink slightly so it isn't making solid contact, which is why it's overheating.
When your FPS takes a massive dive like that, it means the chip is thermal throttling.

What kind of temps are you seeing? Maybe check them with HWMonitor or something.

I didn't actually dismantle the fan; I simply used some tweezers and a vacuum to clear out the heatsink and the fan blades.
The temperature is sitting at 67°C under load. I haven't powered it back up yet, as my plan is to buy some thermal paste, strip it down, and reapply it before seeing how it performs.
Thanks, everyone.

67°C is a solid temperature click
I honestly thought it would be hitting or even exceeding 100, but this isn't bad at all. It’s definitely worth swapping out the thermal paste on such an old GPU that runs this hot (especially if you've never actually done it before)

He applied a heavy dose of "fix-it" grease, and everything is back to normal
thanks again everyone, I don't have enough cash on hand for a second round

Gregory Hayes87 said:He went overboard with the application, and now everything is back to square one.
Thanks again, everyone; I'm officially out of thermal paste for this round.

😂
Just apply a tiny bead or a thin layer click. If you use too much, you're just asking for thermal throttling issues.

By the way, swapping out your paste won't perform any miracles if your ambient temperatures are already within the normal range.

Don't force my hand into stripping it down again.
I definitely overdid it on this one; I spread the coating across the entire surface to ensure nothing peeked through, then just smoothed it out with my finger to keep it thin.