Overclocking Leadtek GeForce 2 GTS 64DDR

[Psychopath]

Okay so, I installed my new ICEBERQ 4 on the card started overclocking..

the base Core clock is 200mhz, and the DDR is 333mhz

anyways, I got as the Core up to 225mhz and the DDR to 360mhz, and anywhere higher i go, i get artifacts...

My geuss is that it's because my memory chips aren't cooled right..

my card has 8 DDR chips and the ICEBERQ only comes with 4 heatsinks, so what i did is put each heatsink on two DDR chips, which doens't really cover them completely.. :\

anyways... what next should i do ?

is there any solution to my problem besides getting more heatsinks for the DDR ?

anything to do with voltage and so on ?.. help me :>