Connect Philips tv to Dell Inspiron Desktop

Hello, everyone. I have a Philips 32PF9731D\10 HD ready tv. I have a Dell Inspiron 531 Desktop with Windows vista Home Premium 32-bit SP2, AMD Athlon 64 by 2 Dual Core Processor 5000+, ATI Radeon HD 2400 PRO. These two have been connected via dvi to hdmi cable for five years no problem. About a month ago, the connection stopped working and I have bought new cables and it still won't work. I can't seem to find the drivers on my computer either, which is odd, though I admit I am not sure what I am looking for. Can anyone please help me to sort this out. I would be very grateful. Tanx in advance of any help offered....(",)**