ATI Radeon X1900 XT and XTX
The world's fastest graphics cards?
For a more in-depth technical appraisal of the R580, head over to Hexus.net here.
The reference board
The ATI Radeon X1900 XT and XTX share an almost identical board to the X1800 XT, although the higher power consumption of the X1900 XTX and XT mean their respective voltage regulation circuits are different.
The XTX reference board uses an identical cooler to X1800 XT, which sadly means the same loud and annoying noise profile when the fan is doing its work. Even the slowest fan setting on X1900 XTX and X1800 XT is noisier than an Nvidia GeForce 7800 GTX 512 reference cooler at full tilt. I'll be looking to the board makers to change the cooler for something quieter.
It's dual-slot, dual DL-DVI-I, with VIVO ability thanks to an on-board ATI Rage Theater 200. Weighing some 700g and measuring the same 228mm long that the X1800 XT does, it's officially physically the heftiest desktop reference board ATI have ever created. A little label confirms that it's an XTX version.
Bereft of clothes you can see the eight 512Mb Samsung BJ11 GDDR3 DRAMs arranged around the chip package. You can find those particular devices on Nvidia GeForce 7800 GTX 512 boards and in Microsoft's Xbox 360.
The fastest GDDR3 that Samsung currently produce and rated to 900MHz, BJ11 is likely the last GDDR 3 speed grade the company will make before shipping GDDR 4 at 1GHz or more in H2 2006. Just one DRAM - 64MB on its own remember - has a data rate of 7.2GBps at 900MHz. This is the bit where you cackle out loud at the big number.
It's worth noting that the rear of the board doesn't get hot, both DVI ports are dual-link capable should you attach something that needs it, the heatsink design still uses skived fins and, while noisy, the heatsink design and fan are more effective than anything Nvidia has made since the infamous FX-Flow at getting heat out of your chassis.
For those things we salute ATI's board and thermal engineers.