Based on your original statement of;
i am NOT a hardcore gamer, so i DON'T want max performance or something like that since i won't be playing all the newest games etc.
For the price you'd pay for a 1GB HD4850, you could get a 512MB HD4870, which would be more than enough for your current (and most likely, future) needs. Don't be fooled by the 512MB/1GB mess. You won't see any benefit of the extra 512MB on the HD4850, as it would be contradicted by the slower GPU and MEMORY speeds.
That being said, if you plan on keeping your next video card for longer than a year, and are really set on having 1GB of memory, then I'd recommend just spending a bit more and going with the HD4870 1GB. There are a number of models priced around $205 - $215 (after rebate), that you'd be very happy with.
As far as the HD4870 ICEQ 4, from what I've read it's nothing more than the stock cooler with fancier plastic and a slightly different blower fan. Don't expect it to be hugely quieter than the reference stock dual-slot cooler. In the case of the HD4850 with the ICEQ 4 cooler, it's actually a good choice, as it is quieter and more effective than the usual single-slot garbage reference cooler, that comes (or used to come) with most HD4850's. Since it exhausts air out of the PC, it's highly recommended, since most HD4850's (now) come with flower coolers that do not do this.
With all of these cards the big difference with regards to cooling and noise output is how the BIOS is set up. With a BIOS that has a properly set up fan speed section, the card can have lower idle fan speeds, and ramp up quietly and in an effective manner, to increase speeds as the GPU temperatures increase. Unfortunately, this is a lost art with many manufacturers, as they just copy the same non-optimized fan settings over on to their newer cards. All is not lost though, as the end user can tweak these settings and/or use third party programs to set the fan speeds to their personal liking....