i wanna buy a 512 Mb RAM.My friends advise me to choose kingston and kingmax.I m kind of confused.Which one is better?

What is your motherboard? Some RAM memories incompatible with some motherboard's models =)

I am not a fan of Kingston. Form what I've seen it is cheep, unreliable memory.

i find kingston to be a quality product,i would go with kingston

I personally would go with neither, I prefer Corsair as they have been around longer than both of those companies and since I've had the same 1GB memory stick from them in my pc for the last 3 years without any problems, that speaks for itself and I'm not saying this for just any reason, I'm a IT technician and sell many memory modules every month and from my personal experience there isn't more reliable memory than Corsair.

Shaun

Also you can buy OCZ Ram, it have high quality.