So is it the wrong time to upgrade cpu?

[Tricky]

You really need to think about the combination of components.

If you get tall RAM you may be limited to the smaller air coolers, or one of the water cooling units from Corsair or Antec, depending on the motherboard layout.

Is this really a consideration?
Can you seriously get different height RAM modules, I thought they were a standard size?
Gets more complicated every minute.

 

[Nightglow]

It's the heat spreader on the memory,with Corsair you can get either Low Profile version
or with a tall heat spreader.

http://www.overclockers.co.uk/showproduct.php?prodid=MY-307-CS&groupid=701&catid=8&subcat=1517

http://www.overclockers.co.uk/showproduct.php?prodid=MY-313-CS&groupid=701&catid=8&subcat=1517

 

[Tricky]

It's the heat spreader on the memory,with Corsair you can get either Low Profile version
or with a tall heat spreader.

http://www.overclockers.co.uk/showproduct.php?prodid=MY-307-CS&groupid=701&catid=8&subcat=1517

http://www.overclockers.co.uk/showproduct.php?prodid=MY-313-CS&groupid=701&catid=8&subcat=1517

To be honest I've not been paying any attention to the pictures of the RAM I've been looking at, good to know.
Many thanks for the heads up.