Noob CPU cooling questions

I'm a noob to overclocking and up till now have always used the stock HSF so please bear with me.

I recently installed a Barton 2500+ with an Aeroflow VA4-C7040 HSF and I think it's running a little hot. Under load the Diode temp is reaching 53 and the Socket 42. Normal running temp is 44 Diode and 37 Socket. These are the temps with the side pannel on the case off and case temp at 19.

One thing I think I did wrong when installing the HSF was applying to much of the goop that came with the Aeroflow. I'm pretty sure a large portion around the chip is covered with the stuff. Will this affect temps? I have a tube of AS3 on the way so when I get it i'm going to follow the directions on their site.

I'm also considering ordering a SLK-800 and a Thermaltake smart fan II. Whats the difference between the SLK-800 and the SLK-800-U? I see the U version comes with some extra parts that go between the heatsink and the CPU. If I were to order the non U version would I need to order any extra parts that would go between the heatsink and the CPU? Could I just put a little AS3 between the two or do I need another part?

Thanks for any advice.

The only real difference between the A and U is...the A clips on and the U is bolted on...so if you do not have a MB that has the four mounting holes around the CPU socket...then you can not use a 800U...

As for the thermal paste...too much can be just as bad as too little...

Follow the directions for aplying AS3...this pretty much works for any thermal paste...

AS3 Link

also make sure it is seated level and evenly making complete contact with the core....also...you might want to use mbm5 and a digidoc or some kind of temperature probe to make sure your mobo is reading correctly, that seems to be the biggest problem with a lot of motherboards recently

i have the exact same proc and hsf using as3 when my rig was at stock thats about the temps i was getting 51-53c load on the die and about 40-41 on the socket the die is always alot hotter because it takes the readings from the actual cpu core not the thermal probe mounted in the socket

those are not that bad of temps.
a SLK800 with a Tt SFII will rock youll see 30ish cpu temps
as for applying thermal grease just make sure not to get any on the chips cut bridges, a little extra wont hurt it or your temps.
AS will be better then the stuff the HSF came with.
just make sure your HS and FAN are mounted properly.
you'll be all good.
-L_P