AMD ATI Radeon HD 4770 512MB

Radeon HD 4770 board design

Core Clock: 750MHz
Memory Clock: 3,200MHz (effective)
Memory: 512MB GDDR5


The Radeon HD 4770 incorporates a dual-slot cooler, which initially came as a bit of a surprise to us – especially when you factor in the price of this card. It’s not a complaint though, as the cooler does a good job of exhausting air out of the chassis, even if the fan does spin up to 100 percent at random intervals.

Under the red shroud, there’s a 100 percent copper heatsink with a pair of heatpipes transferring heat from above the GPU core to the heatsink fins. It’s a fairly traditional take on GPU cooling – especially in this day and age – and is backed up by a 70mm radial blower that is mostly quiet, aside from the aforementioned random spin-ups which are likely to be down to the temperature thresholds in the current firmware. They’ll probably be fixed down the line.


The card itself is 210mm long, which means it’ll fit into even the smallest of cases, as long as there is support for dual-slot graphics card coolers. In fact, it’s the dual-slot cooler that we feel could lead to more than a few debates – it did in the bit-tech offices – because this card is ideally priced to be considered for a media centre or small form factor PC with a decent amount of gaming performance on tap, but the dual-slot cooler may prevent that from happening.

Removing the heatsink reveals the tiny RV740 GPU – it still boggles the mind to think there are 826 million transistors packed into that 11.5mm x 12.5mm piece of silicon. It’s surrounded by eight Qimonda GDDR5 DRAMs running at 800MHz (3,200MHz effective) – these are passively cooled by a black aluminium heatsink that extends out along the top edge of the card.

The power supply to the card is an area where there have been some understandable cost cuttings made – the chokes, of which there are four in total (three for the GPU and one for memory), aren’t environmentally sealed and are of standard height. The PWMs are also the older type as well and there are three per choke – two push and one pull per phase.


There is one low-profile choke up close to the CrossFire connectors, but it’s difficult to work out exactly what that does by simply following traces. What we do know though is that the Renesas R2J2062 MOSFET it’s coupled with can handle up to 40A per channel and it’s the same type of MOSFET MSI uses for its DrMOS power saving technology.

To finish off our discussion of the power end of the board, there’s a lone six-pin PCI-Express power connector which needs to be connected for the card to work. AMD states that the board requires 80W at peak during normal operation, so there’s more than enough power available with 75W going through the PCI-Express slot and another 75W of supplementary power available through the six-pin connector. With this in mind, it’ll be interesting to see how well retail cards overclock.

Moving round to the PCI bracket, the top slot is cut for ventilation, allowing the heatsink to push air out of the rear of the chassis, while the second slot comprises a pair of dual-link DVI connectors that come complete with support for 7.1 channel audio over HDMI and HDCP content protection just in case you want to watch Blu-ray movies on your PC. The bracket is rounded off with an HDTV-out connector located right between the two ports.