At least use a can of compressed air and blow out the case. Do it outside so the house doesn't fill up with dirt. Hold the can away from the target a bit. Keep the air from hitting anything too forceful. You can dislodge small soldered-on components.
Yeah, that's a pretty bad "400W" PSU with its tiny +12v rail. But you should be OK. I ran a GTX 750 Ti and later a GTX 1050 Ti on a 17A rail. Yours at least is 22A.
At least use a can of compressed air and blow out the case. Do it outside so the house doesn't fill up with dirt. Hold the can away from the target a bit. Keep the air from hitting anything too forceful. You can dislodge small soldered-on components.