For the RAM, the CAS2 Kingston should perform better than the CAS2.5 Adata, but I doubt the difference would be as high as the price difference. I'm not familiar with Adata, but as long as they can produce good quality RAM (search for reviews and opinions online), I'd go with the cheaper one.
"my power supply is only 110wts O.o (its an ikkle cute one ^_^)"
um.. is that as in a half sized HP power supply? If so, do you have a mini or mid sized case? HP's smallest PCs are not necessarily upgrade friendly.
I am thinking about getting a Radeon 9600XT (much cheaper than the high end {about CAN$250/£110}, but most of the performance) or possibly a GeForce FX 5700. I'm leaning towards ATI, but have not checked many reviews yet.
