AMD Radeon HD 7750 & HD 7770 Launch Review

Product: AMD Radeon HD 7700 Series
Company: AMD
Author: James Prior
Editor: Charles Oliver
Date: February 14th, 2012

Test System

Our test platform is an all-AMD affair, using AMD FX processor and requisite AM3+/990FX equipped mainboard. Details below:

Component Specification
Mainboard ASUS R.o.G. Formula Crosshair V
Processor FX-8150 3.6GHz/4.2GHz Turbo
Graphics Card AMD Radeon HD 7770 GHZ Edition
  AMD Radeon HD 7750
  Sapphire Radeon HD 6850
  Sapphire Radeon HD 6770 VaporX
Memory 2x4GB AMD Radeon Entertainment DDR3-1600
Audio Creative X-Fi MB 2
PSU Corsair HX850
Case CoolerMaster HAF 932
Storage Corsair Force 120 + Seagate 7200.12 1TB
Heatsink/Fan AMD FX Liquid Cooler
Display Dell P2210H
Operating System Windows 7 64-bit Ultimate SP1
Driver Catalyst 12.2 Preview
  Cape Verde: 8.932.2

Below you can see the AMD Radeon HD 7770 inside our test system:

Cape Verde XT / R7770 GHz Edition

Radeon HD 7770

Thankfully, no leaf blower fan - instead a delightful red axial fan, which vents both out of the case and back in. With an 80W TDP that's not really a huge additional heatload, especially not next to that Bulldozer ...

The PCB layout looks fairly simple and uncluttered, although a lot of rear mounted components mean care needs to be taken not to knock off important parts when handling the card. The heatsink is retained by a spring backplane clip, familiar to long-time users of AMD Radeon reference products.

Yep, that tiny shiny thing is the GPU core. Power appears to be three phases for the ASIC and one for memory, with four memory chips providing the 1GB of GDDR5. The chips appear to be rated to 5Gbps, so overclocking from the stock 1.125GHz should be easy. The heatsink is a solid aluminum design to which the fan is mounted, with a plastic shroud to give shape to airflow.

Radeon HD 7750

The Radeon HD 7750 slims down to a smaller, shorter PCB and is single slot cooled. AMD opted for three full-size outputs, although there will surely be variants with single DVI and 3 mDP for productivity/video conferencing/presentation use. No backplate spring clip for the heatsink this time, just four spring mounted screws.

Note the absent CrossFireX connector, instead relying on PCIe slot bandwidth for multi-GPU. With PCIe 3.0 support, that shouldn't be an issue, and likely PCIe 2.0 x8 slots will offer enough bandwidth to support Cape Verde Pro multi-GPU. Along with the PCIe power connector, we also appear to lose a power phase. Again the memory appears to be 1.2GHz specification, giving us hope for overclocking.

For today's comparison, we use the two outgoing models that these cards challenge - the AMD Radeon HD 6850 and AMD Radeon HD 6770.

Product Specification Comparison

  HD 7770 HD 7750 HD 6850 HD 6770
SEP (USD) $159 $109 $134 $129
Engine Clock 1000MHz 800MHz 775MHz 860MHz
Memory Capacity 1GB 1GB 1GB 1GB
Memory Speed 1125MHz / 4.5Gbps QDR 1125MHz / 4.5Gbps QDR 1000MHz / 4Gbps QDR 1200MHz / 4.6Gbps QDR
Power <3W / 80W <3W / 55W 19W / 127W 20W / 108W

Our competition today has custom cooling and even a mild overclock on the VaporX, just to keep a bit more heat on the new cards.