stacking a PowerConnect 3548 and 3524

Hii
I'm setting up a test lab in office and found 2 PowerConnect switches (a 3524 & a 3548)
I know it can do stacking through ports G3/G4 but i can't seem to get it to work..hope someone can enlighten me~

Here's what i've done/tried:
Connect straight network cable from port G3 of 3548 to port G4 of 3524. Reloaded the units.
Assign address to 3548, login to console but under Stack Management, shows a single unit..Also LED infront (Stack ID) does not light up.
Thought i might need to close the stacking loop?? so even tried to connect a cable from G4 of 3548 to G3 of 3524. But also doesn't work.

Am i connecting them wrongly?

Thanks much in advance!~