Introduction

In more recent years, gamers have increasingly turned up their screen resolutions and turned on eye candy features such as anti-aliasing and anisotropic filtering, while game developers have incorporated higher resolution textures and normal maps into their latest titles. As a result of these developments, the demands on the memory subsystem of today’s graphics cards has never been greater. More data is being pushed that ever before: not only do you need faster memory to maintain fluid performance, you also need more memory on the graphics card in order to keep the graphics core fed or else your performance will begin to chug.

512MB of gaming bliss

The X850 XT 512MB HD running in a water-cooled system with unannounced ATI motherboard

The back of the 512MB card

In mid 2003, graphics card manufacturers began to incorporate 256MB into their high-end gaming cards. While initially only one or two games were capable of taking advantage of the extra memory, over time more demanding games were released; today there are numerous examples out there.

Now games are going to the next level, Epic’s next generation Unreal engine demonstration stunned everyone last year, but that was only a glimpse of what you’ll see in final games based on Unreal Engine 3. DOOM 3’s Ultra Quality mode runs everything at full resolution, with no compression, in a .plan file from last July, id’s Robert Duffy said “In Ultra quality, we load each texture; diffuse, specular, normal map at full resolution with no compression. In a typical DOOM 3 level, this can hover around a whopping 500MB of texture data. This will run on current hardware but obviously we cannot fit 500MB of texture data onto a 256MB card and the amount of texture data referenced in a give scene per frame ( 60 times a second ) can easily be 50MB+. This can cause some choppiness as a lot of memory bandwidth is being consumed. It does however look fantastic :-) and it is certainly playable on high end systems but due to the hitching that can occur we chose to require a 512MB Video card before setting this automatically.”

To address this, ATI has developed their 3Dc normal map compression technology, but they’ve also developed another solution: integrating 512MB of graphics memory into their latest graphics cards.

Dual slot cooling still present on the card

Another shot of the system with 512MB card

Memory modules are no longer covered by heatsink

Yesterday at the Texas Gaming Festival in Dallas, Texas, ATI demonstrated their first generation of 512MB cards, the RADEON X850 XT 512MB HD. As its name implies, the X850 XT 512MB HD is based on ATI’s RADEON X850 XT VPU, which is clocked at 520MHz core/540MHz memory. ATI outfits the board with 512MB of GDDR3 memory, using the same 8Mx32 modules used on X850 XT cards today.

A Sapphire X850 XT 256MB, note the memory modules are covered

Memory modules on the back of the X850 XT 512MB

Now the 256MB Sapphire X850 XT card, no modules in place on the back.

Since memory modules of the same density are used, ATI had to retune the R480’s memory controller to properly address the additional memory with a minimal performance impact, without this the added memory would have introduced additional latency, hampering performance. Physically, you’ll see the return of double-sided memory, as the 512MB X850 XT card has memory modules on both sides of the board’s PCB. Other than this change however, the X850 XT 512MB HD looks practically identical to previous X850 XT boards, right down to the same dual-slot cooling.

A shot from ATI of the X850 XT 512MB reference card

The top of the X850 XT 512MB card