Arduino UNO R3 problems error

Hello. I've bought an Uno R3 with ATMEGA328P-PU and Atemga 8U2. I play a litlle, and i do a mistake and suddenly i received an error avrdude: stk500_getsync(): not in sync: resp=0x00.
I try diffrent things. My pc appear to reconize only the communication port, and no arduino uno. I try to unplug the atmega 328 and make a short between RX and TX, but when i send data from serial monitor, the Rx led blinks, but Tx nope and no data came to pc, of course.

It's only the 328 damaged? Or both atmega are dead?

Give oppionons please, and sorry for my bad english!

Are you using the latest Arduino software?? I had this problem on a machine with Vista installed and Arduino 022, as soon as I installed Arduino 1.01 it found the drivers. You need to find from Device Manager the correct drivers by doing driver update in DM and pointing it to the Arduino drivers folder.