Accelero x2 not giving desired performance?

I dont know your computer building skills and I am just offering suggestions...
**Did you put thermal paste on the GPU before you put the heatsink on?

**Did you make sure the fan was plugged in on the heatsink?

**Did you maybe disconnect any case fans?

**Maybe you should consider using artic silver... it only helps for 1 or 2 degrees Celcius but... it could help

**Have you recently watercooled your CPU? If you have.... the cpu fan is no longer there so you lose the airflow over your motherboard... and if you installed a radiator to the back of your case where the fans used to go that would also cause problems exhuasting the hot air.

**If you overclocked after putting on the heatsink that would definatly raise temps

**Did you forget to take the thin plastic layer covering the copper parts protecting the heatsink?

These are just suggestions and I dont mean to make you sound stupid or anything, I just tried to think of EVERYTHING that could possibly be causing the increase of temp over stock. Goodluck fixing your problem buddy!

It may take a few trys to get it right. I'm guessing you still may have some air pockets between the gpu and hs.

I remember trying AS5 on my Zalman VF700 on my 6800GS (AGP). I didn't get any great results since I was trying to use little amount. I was thinking the same thing was happening to me at the time(air pockets), since I was getting the same temps as my stock HSF.

So rather then re-doing it so many times, I ended up using the thermal compound that came with my zalman, which in turn I was happy enough with its results. Which is about the same as your stock temps (47C idle ~ 57-59C load)

I suppose if you try the regular thermal compound to see what temps you would get on that Accelero. That way you can compare your application install between the two compounds. Maybe redo your AS5 later to get a good comparison on how much to use to fill the air gap.