Optiplex 755 SFF heatsink

Hello, I've just got a Q9650 cpu for my Optiplex 755 SFF and now i'm wondering about the cooling system.

I'm not so expert I'm looking for some helps to understand if I need an upgrade of the original heatsink or not since I read the new cpu has 75w of TDP.

So can someone please tell me:

1) is the original heatsink enought to manage Q9650 cpu?

2) any suggested better heatskink system? possibly the silent as possible (preferred a passive one but ok also for air/liquid if with a passive is not enought)

Thank you all in advance