Ah thats no worry, I've a mountain of cable ties, a Full tower case and Ill try to use as many of the leads as I can.
you will be fine especially since you plan to use three HDD, you will end up using most of the cables anyways. Ive built plenty of PCs using both modular and non and find little difference between the two (at best on a minimal hardware PC i may save one to two cables)
most motherboards now use a 24 pin mobo connector and a 4 pin or 8 pin CPU power connector. they have used that set up for some time although older mobos used 20 pin power connectors.
some older hardware use molex power connectors while newer hardware uses SATA. most modern graphics card use a 6 pin or 8 pin power connector.
your corsair will be able to handle any of those set ups.