PSU connector types required on HP Pavilion t550.uk

I need to replace the power supply in my HP Pavilion t550.uk in order to accommodate a new graphics card requiring 300watt. The existing PSU I believe is a BESTEC ATX-250-12Z REC:C.

Opening the machine up there seem to be 5 existing connections:

1) DVD and CD drives - these both have a rectangular connector with 4 x 1 sections and 8 wires

2) Hard Drive - this is very similar to the above but perhaps a little larger in size.

3) Motherboard - a large rectangular connector with 10 x 2 sections. Many wires.

4) Motherboard - a square connector 2 x 2 with 4 wires.

The new graphics card also requires a 4 pin connection.

The dimensions of the existing power supply are 6 inches x 5 1/2 inches x 3 1/2 inches.

I was considering an Antec E380 or something similar but I am concerned about the type of connectors I need. I think the existing motherboard connectors are compatible with most modern power supplies but I’m unsure about the others.

Other than http://www.itwinkle.com/be25posuba.html , which is not the exact same model, I can’t find any specs online describing the connectors on the Bestec. Here they are described as 4 x PATA.

- The Antec has 6 x Molex (and 4 x SATA, which look completely different to me). http://www.antec.com/connectors.php?ProdID=04639

- The Cosair 430CX has 3 x 4 Pin Peripheral Connectors (and 4 x SATA).

Are these Molex or 4 Pin Peripheral Connectors what I need or do I need to look for alternatives or adapters perhaps?

Would appreciate some guidance.

Thanks