Did you mean a total of 4 drives? Or just one of each? If you meant one of each on each channel, you may either need longer cables as the distance between the drive connectors on the std 18" cable is only 6" which may be tight since the HD bays are at a right angle to the optical bays on the BQE (but 24" should be fine) or mount your HDs with 3.5 to 5" adapter brackets and mount all the drives in the 5" bays. Then std cables would work. Or if your mobo has SATA connections, you could use those for HDs and std IDE channels for opticals - I actually think that that was the plan in the design of the BQE and all the others made on that same basic design (Enermax, Aspire, etc). Then each drive would have its own channel which is optimum for IDE. The layout of the 3700AMB and others based on the same design (Compucase 6Axx series, etc.) where the drives are all the same direction would be better for normal IDE drive cables.
.bh.