Unfortunately, this is not a takeover. TDFX sold assets and its going to shut it's doors. It appears that you will not receive NVDA stock. I've pasted a news article for you. TDFX will simply keep the cash made from the sale of assets to pay off creditors.
3Dfx Chief Executive and President Alex Leupp said in a prepared statement: "After aggressively pursuing a wide range of options that take into consideration the interests of our creditors, our shareholders, our employees and our customers, we strongly believe that to reduce expenses, sell our assets and dissolve the company provides the highest return ... ."
To find out more look up a stock quote and check the news for TDFX