Intel Core2 Quad Q9550 VS I5s

Hey

Im in a place i need to change my CPU from Core Duo 7600

I already got 775 MOBO.

I was wondering if I5 is worth more than Q9550 becouse i will need to buy new MOBO and RAM to get I5, and I've already got P5B Premium and RAM ready for Q9550.

Quad will cost me 100$ and I5 wil set me back 500-600$ including new RAM and MOBO

Is it worth to pay so much?

I'd say the i5 is definitely worth it. The Core 2 Quads are still decent processors, but they're definitely starting to show their age. Their performance is about the same as an AMD Phenom II, so it's going to be a bottleneck for more modern hardware. The i5 isn't going to bottleneck anything and will definitely be a much better long term investment.