Q9550 or 9650

Q9550 can clock to 4.0Ghz also, but you will need a good quad overclocking board such as the Gigabyte UD3P.

Reason being is that you will need to be able to get high FSB.

Q9550 here. 4.0 stable; 4.2 "sorta" stable...lol Games fine at that frequency, but Prime95 gets errors after an hour or 2.

I suppose I could pump more voltage through it?... but I want to keep to Intel specs on it.

The thing is: Are you looking for a number, or are you looking for clearly defined operational improvement. I ask as I see little if any difference in all my day-today tasks when running 3.8 - 4.0. But, then again I am only gaming, surfing, listening to music... nothing really intensive.

4G is doable for 8.5x Q9550 but fsb needs 470+ so you need a high fsb board such as UD3P. I got one for my friend two weeks ago. It is stable at 475*8.5 but could not go beyond that.

I would recommend the GA-EP45-UD3P even with a Q9650.. it is the only board that has stabilized my chip above 4G !

Just make sure everything is kept nice and cool!

It would also depend if you want to pay the extra $50(at the egg)for 170MHz and a 9x vs 8.5x multiplier. If it were me, I'd get the 9550. A good cooler on a UD3P should get you 4.0 on the 9550. However "cool" 4GHz is, the diff between 3.8 and 4 is not that significant.

Actually the price difference is almost $75. Personally, the Q9650 has tons more OCing potential, but the Q9550 is pretty much a 4ghz chip.

Well I have the UD3P already so I know I can OC the hell out of these. So I think I'll go with the 9650.

Dependent on:

your board
budget

Between the two I'd go 9550 with a good board. However, if you have the money for a new i7 board and ddr3 ram, go 7. The chips are the same price and the performance is much greater.

I think the money spent on the 9650 is waisted.

Spend the price dif on a good cooler for the 9550, if your board can get to higher FSB than you are golden. Most people are able to hit the same speeds as the 9650 anyway.

If you want to oc higher go with the q9650 if you are going to just do moderate oc'ing just go with the q9550

I would go here http://www.newegg.com/Product/Produc...Size=10&page=1

Look at some of the combos that newegg has for the q9650 if you need something besides the cpu i would go for one of the q9650 combos If you only need the cpu and don't plan to overclock heavy just go for the q9550

My Q9550 is running at 3.83 with an Asus Maximus II Formula. Haven't gotten around to trying for 4GHz yet.