Most users will assume that HD 4730 will be “weakened” HD 4770 and that only uncertainty will be amount of “degradation”. As surprise, HD 4730 is far from this assumption. Radeon HD 4730 follows entirely different business logic. Before all, HD 4730 isn’t based on 40nm GPU that is used on 4770, but instead “old” 55nm RV770 GPUs are used. This is one of the specs that HD 4730 is sharing with its older HD 4830 brother. This is indeed an interesting twist in this story, since we all hopped that ATI will continue with implementation of 40nm manufacturing process. Maybe we were simply too optimistic when it comes to progress toward 40nm manufacturing process, but nevertheless we are little bit disappointed. But this is not a complete story about new HD 4730. If only difference was lack of 160 Stream Processors it wouldn’t be too bad. Since HD 4730 is made with lot of compromises in its engineering process some problems are noticeable from the start. Memory bus of 128bit is successfully “patched” with GDDR5 memory.

This resulted in, effectively, doubled memory bandwidth so we don’t expect too much problems in that department since PCB used for HD 4730 is the same one used on HD 4870 models that was designed for 256bit memory bus. Because of this, only half of memory “slots” are used. This resulted in another compromise: number of ROPs is halved. From 16 to, very low, 8 which reflected on performances. If you asked yourself why this wasn’t problem on HD 4770 we will remind you that HD 4770 was optimized PCB for 256bit memory bus so all ROPs can be used. Another drawback of HD 4730 is older GPU that comes with large PCB for this class of product. Card itself looks bulky and it uses two 6-pin power connectors, which isn’t good news since these cards will be used in cheaper configurations that very often don’t have powerful PSUs (Power Supply Units). We didn’t get official info on power consumption of HD 4730 but we came out with not so good news: it uses as much power as one HD 4870! Because of all this, we can only conclude that HD 4730 is “transitional” model and that its market “longevity” will be short.