GDDR5
The Radeon HD 4870 uses GDDR5 at 900 MHz for commands, it means 1800 MHz for data transfer. All the Radeon HD 4870s tested here have identical Qimonda memory modules. To be precise they are IDGV51-05A1F1C-40X modules certified at 1000 MHz for the command clock. Qimonda says that IDGV51-05A1F1C-50X modules, certified at 1250 MHz, are in production but no manufacturer uses them yet.
GDDR5 is identical on all the Radeon HD 4870s.
512 MB or 1 GB?
Generally speaking, 512 MB versions are enough. If however you want to play at 2560x1600 or 1920x1200 with antialiasing, the additional memory may be useful in some cases and will become more and more so in the future.
You therefore should make your choice depending on how long you intend to keep your graphics card. If you are intending to change the card as soon as the first DirectX 11s appear you’ll be better off staying at 512 MB than if you intend keeping it for over a year.
Note that GDDR5 memory chips are available in 2 densities: 64 MB and 128 MB. The basic Radeon HD 4870 has 8 64 MB modules to make up the 512 MBs. You can simply replace them with their 128 MB equivalents if you want to move up to 1 GB, without having to modify the PCB. The 512 MB and 1 GB reference cards are therefore identical.
On the left, a 64 MB module and on the right the equivalent 128 MB module.
Test protocol
For this test we used the same protocol on graphics cards and temperature management , which gave us a detailed analysis of the impact of the choices of the different AMD manufacturing partners in this respect. A small difference with that report is that the CPU we’ve used here is a Core 2 Duo E7200 and not a Core 2 Quad Q6600.
Infrared thermography: graphics cards at rest
Stock Radeon HD 4870
Asus EAH4870 DK TOP
MSI HD 4870
Infrared thermography: graphics cards in load
Stock Radeon HD 4870
Asus EAH4870 DK TOP
MSI HD 4870
Infrared thermography: systems at rest
Stock Radeon HD 4870
Asus EAH4870 DK TOP
MSI HD 4870
Infrared thermography: systems in load
Stock Radeon HD 4870
Asus EAH4870 DK TOP
MSI HD 4870
Key tags :
Radeon HD4870,
GDDR5,
Core 2 Quad,
GeForce
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