Power supply requirement for Nvidia Geforce 7900 G

Hello all. I just purchased 2 MSI nvidia geforce 7900 GS PCI-E video
cards that I intend to use in SLI mode in replacement of my current
nvidia geforce 6800 GS PCI-E in SLI mode. the geforce 6800 GS don't
require external power but the geforce 7900 GS cards do. My current
power supply is a PC Power & Cooling Turbo cool 510XE 510 Watts (650
watts total) which I think is the best power supply in it's class. It
is not a SLI power supply, it has only one PCI-E Power connector but I
have a molex drive wye PCI-E connector for a second card for SLI. I
don't know whether or not my current power supply is enough. I'm eyeing
another pc power & cooling power supply, the SILENCER® 750 EPS12V 750
watt PSU which is a SLI certified PSU. So I need to know whether or not
my current PSU will be suffiicient. Give me your suggestions and
comments. Here is my current computer configuration.

M/B: MSI K8N Neo 4 Platinum/SLI
CPU: AMD Athlon 64 X2 4800+
CPU Cooling: Thermaltake Bigwater cpu water cooling system
Memory: 1 gigabyte of Corsair CMXP512-3200XL
1 Gigabyte of Corsair CMX512-3200C2 2 Gigabytes total
Graphics cards: 2x Nvidia Geforce 6800 GS PCI-E in SLI mode
Sound Card: Creative Labs soundblaster X-FI platinum
Optical Drive #1: LG GDR-8164B Internal DVD-ROM
Optical Drive #2 Plextor PX-716A DVD-R
Hard Drive: 2x Western Digital Raptor 74 Gig 10,000rpm in RAID 0
configuration
Floppy Drive: Mitsumi 1.44 Floppy Drive
Temp Sensor: Lian Li TR-3A Thermometer
Case: Lian Li PC-V1200 (Modified with window kit)
Fans: 3 120mm fans and 1 80mm fans
UV: 2 UV lights so it looks cool.
Wireless LAN: MSI MS-6852 PCI Dual net card

Here are my curent PSU specs. shifty.gif

PC Power & Cooling 510W Turbo Cool PCI Express PSU T51EX
Connections
1 x 24-pin Mainboard
1 x 24-pin to 20-pin Adapter
1 x 4-pin P4
1 x 6-pin PCI Express
6 x 5-pin SATA With 3.3V Line
8 x 4-pin Molex
1 x 4-pin FDD

Features
Shielded EMI Filter and Large Input Inductor provides superior high and
mid-frequency noise suppression
Large Input Capacitors and Power Factor Correction Circuit provide line
conditioning, longer hold-up time, and lower input current
Heavy-Duty Heat Sinks, Transformer, and a High-Capacity Ball-Bearing
Fan means it will run cooler with more power, and a longer life
Independent Regulation provides superior rock-solid voltage stability
+3.3, +5, +12 Voltage and Over-Current Adjustments provide precision
control and system fine tuning
Heavy-Duty Output Capacitors provide superior noise and ripple
suppression
Thermal Protection and Fan Speed Control provide fail-safe protection
and quiet operation

Specifications:
AC Input:
Operating Range: 90-564 VAC, 0.99 Power Factor Auto-Select
Frequency: 47-63Hz
Current: 10A @ 115V
Efficiency: 70%
EMI: FCC-B, CE
DC Output:
Output:
+5V: 40A
+12V: 34A, 38A pk
-5V: 0.3A
-12V: 2A
+3.3V: 30A
+5VSB: 3A
Power Output: 510W
Peak Power Output: 650W
Regulation:
+5V: 1%
+12V: 1%
-5V: 5%
-12V: 5%
+3.3V: 1%
p-p: 1%
Hold Time: 20ms
PG Delay: 300ms
Safety:
OV Protection: +3.3V, +5V, +12V
OC Protection: +3.3V, +5V, +12V, -5V, -12V OCP
Agency Approval: UL, ULC, TUV, CE
Environmental:
Temperatu 0-50° C
Humidity: 10%-90% RH
Fan Type: 30-44 CFM ball
Noise: 30-44dBA
Miscellaneous:
Compatibility: ATX12V (2.03)
M/B Connectors: 20-pin/24-pin, 4-pin P4, 6-pin PCI Express
Drive Connectors: 15 (6 SATA, 1 mini)
MTBF: 100,000 hrs
Dimensions: 5.9" x 3.4" x 5.5" (W x H x D)

Holy Cat!

johns

Anyway, you might not like the 7900 fan noise.
Z-cooler VF900 is what I have, and it is very quiet.
Not a clue on the psupply. I would just try it and
see. If it is not enough, you'll get blue screens
in games. The 7900 is suppose to be low power
compared to the 7800, but I notice that NewEgg
says right up front 450 watts minimum. I have
the 480 watt Truepower, and it works fine.
Also, I have a test box .. Dell 9150 with a 7900
in it. The Dell driver quietens the fan noise of
the 7900, but it comes back if I run AutoCAD.

johns