I've bought an ASUS GTX 750Ti OC and tried to install it into my computer, in the PCI-E x16 slot but there is this 6-pin power thingy on top of the card.. In which case I don't have in my machine atm., I've ordered a 2x4-pin to 6-pin molex.

Here is what I've tried so far:

- I've replaced my old card with my new card without a 6-pin power thingy. (The little LED turned Red)
- Tried to plug a 6-pin from another power supply from another old computer, than from my computer. (The little LED turned Green)
Nothing on the screen.
- I tried to plug a VGA cable from the motherboard's output. (Tried to go to dxdiag, showing nothing about a new card, no driver either.)

I gave up at last. Couldn't think of any other ways.

Specs:
Processor: AMD Phenom X3 8550 @ 2.21 GHz. 1 processor, 3 cores
Motherboard: PEGATRON CORPORATION NARRA3
Memory: 4096 MB DDR2 SDRAM 402MHz
Power Supply: HP 300W POWER SUPPLY 5188-2625 DPS-300AB HP-D3057F3R