Some Aurora R4 Shipped with an 875W power supply unit  J556T W299G

You can tell from the Part number on the supply which it is.

There is also Dell OEM SLI (RKT14)  or CrossFireX (PJG49) bridge used for 2 cards.

Typical Component list

Part Number    Quantity  Description
F836R          1         PAD, MOUSE, ANW, M17X
5120P          1         CORD, POWER, 125V, 6FT, SPT2, UNSHIELDED
7P4JG          1         ASSEMBLY, HEATSINK, H2C, CENTRAL PROCESSOR UNIT, AUR4
TXVT9          1         Assembly, Dvd+/-Rw And Bd-Rom, 8X, Hitachi Lg Data Storage, AACS
8WDYM          1         HARD DRIVE, 1TB, S3, 7.2K, SGT-PHAR6G
GH3N9          2         CARD (CIRCUIT), GRAPHICS, RADEON, HARD DRIVE, 6870, BMP
R4DW2          1         Kit, Software, RME, 1.6, Powerdvd, 3D, 9.6
J8461          1         ASSEMBLY, CABLE, VIDEO, LEAD FREE
P895N          1         Kit, Keyboard, Universal Serial Bus, United States, KG900, T1
5CXH7          1         PROCESSOR, SNB, I7-3820, 3.6, 130W, M1 VIDEO CABLE, 4C
VT8FP          4         DUAL IN-LINE MEMORY MODULE, 4G, 1600, 256X64, 8, 240, 2RX8
PJG49          1         ASSEMBLY, CARD (CIRCUIT), AMD, BRIDGE, DUAL
KKMH5          1         Kit, Mouse, Universal Serial Bus, MG100, T1
8WDYM          1         HARD DRIVE, 1TB, S3, 7.2K, SGT-PHAR6G
40DV6          1         KIT, SOFTWARE, W7HP64SP1, MUL17, ANW
1N03G          1         CHASSIS, PWA INTEGRATED, STANDARD, MBK, 875, AUR4
VHGFF          1         CABLE, MINIATURE, DELL PLUS, DELL PLUS, AMD
C439M          1         KIT, HOUSING, CARRIER, FLEXIBLE, AUR
W812M          1         ASSEMBLY, FlSh USB, READER, ENHANCED, BARE, IOI