Power Supply Explanation

[adamsonm]

I recently built a computer. The problem I'm having is that the screen goes a dark green colour with vertical lines across it. There is nothing wrong with my graphics card because I have had it tested by the shop that I bought it from. The graphics card is a Sapphire Ati 5830.
The power requirements are, http://www.sapphiretech.com/presenta...&pid=322&lid=1

I'm wondering whether its my power supply. I have a Corsair 650 Watt power supply.
Here are the specs, http://www.newegg.com/Product/Produc...82E16817139005
My question to you guys is whether its my power supply? Also, the sapphire site says that I need 2 X 75Watt 6-pin PCI Express power connector. What does that mean, and what do I look for in the power supply specs to make sure I am buying what I require?
My system specs are as follows:

Windows 7 x64 Bit
Motherboard - Gigabyte GA-X58A-UD3R, Intel X58, S1366, SLi/Xfire PCI-E 2.0, DDR3 2200/1333, SATA 6Gb/s, RAID, ATX
Processor - Intel Corei7 920 D0 SLBEJ Bloomfield 45nm, 2.66 GHz, QPI 4.8GT/s, 8MB Cache, 20x Ratio, 130W
Graphics Card - Sapphire Ati Radeon HD 5830
Power Supply - 650W Corsair CMPSU-650TX, single 12V rail
Case - Lancool K62 Black Advanced Tower
Optical Drive - Sony AD-7241S-0B 24x DVD±R
CPU Cooler (Heatsink) - Corsair H50
Harddrives - 1TB Samsung HD103SJ Spinpoint F3, SATA 3Gb/s, 7200rpm, 32MB Cache, 8.9 ms and 2TB Samsung HD203WI F3EG
Wireless Card - Edimax EW-7728In 300Mbps PCI
RAM - 4GB 2X2G CMX4GX3M2A1600C9
Monitor - Viewsonic VX2260WM
Speakers - Logitech Z323
Keyboard - Logitech G15
Logitech G500

[kalniel]

Also, the sapphire site says that I need 2 X 75Watt 6-pin PCI Express power connector. What does that mean,

How are you connecting your graphics card at the moment? It has two 6-pin connectors at the end of the card that need to be connected to the power supply via a PCI-E power connector (x2) - your PSU should have a cable or two with this connector on the end.

[adamsonm]

What I did the first time when I connected the graphics card was to use those 2 cables that connect straight to the graphics card without any adapters (The PCI-E conectors). That kept giving me the dark green screen and vertical lines. So what I did was to only connect one of the 2 cables, and then use the adapter that came with the graphics card, the adapter plugs into the cables that I use to connect the power to my hardrives and optical drives. That also gives me the dark green screen with vertical lines. Hope that makes sense.

[ManniX]

This is a pretty obvious sign of a sick GFX card. I know you say the shop you bought it from has tested it but I would be unconvinced personally.

Have you got any spare gfx cards laying around you can swap out for testing? Likewise, a second test machine would be useful. You could try updating the drivers but I doubt it will help. You can use VGA mode for troubleshooting drivers. I'd be surprised if it's the PSU, it should power it fine.

Your motherboard has 4 PCIe slots, try switching it into a different slot.

Where did you buy it from? Are you sure they tested it for you and didn't just claim to? If you can do troubleshooting yourself it would be better.