Bitcoin wallet shows empty after I installed Windows on SSD
Depending on how recently you purchased/mined your bitcoins, the fact that your client hasn't synced might be why you don't see any balance being shown. 

The reason for this is that your wallet doesn't actually contain any physical data representing coins, it simply contains keys that allow you to spend the values associated with a specific address. The way that the bitcoin network determines the number of coins associated with an address is by traversing the entire blockchain and summing all of the transactions including that address. When the bitcoin qt client is syncing, it is downloading this blockchain. Therefore, if all of your transactions happened in the blocks that you have not downloaded yet, it will look like your wallet contains no coins.

This means that the solution to your problem may be to just wait until the bitcoin client has fully synced. If/when your client downloads the blocks with your transactions in them, your balance will be updated. If your client syncs and you do not see your balance change, that means that the bitcoin client is not reading the correct wallet. Make sure that you have copied the wallet.dat file from your old hard drive to the correct place on your new one. NOTE: Make sure that the bitcoin client is CLOSED when you copy the wallet.dat file.

If your client has fully synced and you are sure that the correct wallet.dat file is loaded, and you still do not see your balance updated then you are probably out of luck. If you have lost the cryptographic keys stored in your wallet.dat file, the damage has already been permanently done.