Case swap and upgrade problem!

[slfranke]

Hi, I just swapped this:

Case: Antec 900 .
MOBO: ASUS P7P55D-E Pro LGA 1156 Intel P55 SATA 6Gb/s USB 3.0 ATX
CPU: Intel Core i5-750 Lynnfield 2.66GHz LGA 1156 95W
Cooler: COOLER MASTER Hyper 212 Plus
RAM: G.SKILL ECO Series 4GB (2 x 2GB)
SSD: Intel x25m 80gb
HD: Seagate 7200.12 500GB 7200 RPM
GPU: SAPPHIRE Radeon HD 5850
PS: CORSAIR CMPSU-750TX 750W

into this:

Case: Antec 1200

and added this:

HD: 2 x Seagate Barracuda Green ST2000DL003 2TB 5900 RPM SATA 6.0Gb
GPU: Additional 5850
------------------------------

Now, when I hit power, there is a high pitched (seemingly a warning) sound blaring and the VGA LED on the motherboard stays on. The CPU LED, and BOOT LED and MEM OK LED all come on for a few seconds each too but they go out so I don't know if that happens every time you start the computer anyway. But, the VGA LED stays on and the noise seems to be coming from the GPU but I'm not sure, nothing comes up on the monitor either.

I'm thinking it could be the PSU but I feel like 750w is sufficient for that setup.

Any ideas? This is very frustrating.

THANKS!!!

 

[slfranke]

I am an idiot. I only plugged one PCI power cable into each GPU... Plugged both in and now its perfectly fine... Thanks anyway! Sorry