Manufacturers Ramp Up GDDR5 Speeds, Production

Manufacturers have started ramping up the production of GDDR5 this quarter. Qimonda was the first out of the gate with AMD's Radeon HD 4870. Now Samsung & Hynix have also begun production of GDDR5. Aside from improving availability and driving GDDR5 costs down, the speeds have also started to ramp up nicely.

The Qimonda GDDR5 chips used in the Radeon HD 4870 were rated at 4GHz effective (1GHz quad-pumped) but AMD chose be conservative and clocked them at 3.6GHz. This gives the 4870 an effective bandwidth of 115.2GB/s. That is 81% of the GTX280's memory bandwidth with a 50% smaller bus-width. In my opinion, that is one of the key reasons for 4870 being such a huge success for AMD. They took a risk designing a smaller GPU and combining it with blazing fast GDDR5 memory, in the end it paid off significantly.

Hynix is in the process of producing GDDR5 modules at 5GHz while Samsung has gone further by promising 6GHz modules this quarter. The samples are already available to AMD, Nvidia & Intel (surprise!) and we will be seeing a barrage of new GPUs sporting GDDR5 for the next couple of years. This gives Nvidia the option (Plan B) of ditching the 512-bit bus width for their flagship GPU and still be able to deliver the same class of performance. In fact, Nvidia's current architecture is such that it can deliver similar performance even with lower memory bandwidth. Case in point is 8800GTX & 9800GTX; similar performance from both products but the 9800GTX has 81% of 8800GTX's bandwidth.

When GDDR4 was introduced two years ago, it failed to take off and with such good support of manufacturers for GDDR5, it is bound to take the market share crown from GDDR3 by 2011. The performance benefits offered by GDDR5; 2-3 times the speeds of GDDR3 while offering lower power consumption are too good to be ignored. Current costs are 20-40% more than GDDR3 depending on the memory speed and density (512MiB, 1GiB), but this will eventually go down as these production ramps up and availability gets better.

Performance mainstream products such as the Geforce GT250 (9600GT successor) or the Radeon HD 4670 (3650 successor) could potentially still be utilizing a 128-bit bus coupled with GDDR5. The nett result is that a very cost-effective solution (less layer PCB, smaller die) that could still provide a very respectable gaming performance.

GDDR5 debut was a resounding success, its merits enable it for adoption into various segments effortlessly. Dont be surprised if you find more products in the market based on GDDR5 than GDDR4 this holiday season.

Stumble it!