For testing out the Sapphire Radeon HD 4850 Toxic 512MB graphics card, the system we used was made up of an Intel Core 2 Duo E8400 operating at 4.02GHz, ASUS P5E64 WS Professional motherboard (Intel X38), 2GB of OCZ DDR3-1333MHz memory, Western Digital 160GB SATA 2.0 hard drive, and OCZ EliteXStream 800W PSU. Ubuntu 8.04 LTS with the Linux 2.6.24 kernel and X Server 1.4.1 pre-release were used on the software side. Additionally, the ATI Linux driver used was Catalyst 8.6. Catalyst 8.6 was used over Catalyst 8.7 due to stability issues and segmentation faults we had experienced.
For comparing the performance of this graphics card we had run it up against the Diamond Radeon HD 4850 512MB and Sapphire Radeon HD 4870 512MB graphics cards, which both ran at AMD's reference frequencies. No CrossFire testing was done with the Radeon HD 4850 Toxic as we only had one of these graphics cards and AMD has yet to publicly deliver its CrossFire-supportive Linux driver.