PATA IDE Connections

[andysa1966]

I have two aging MDD G4's, one dedicated to OS9, Xserve 1.33 OC to 1.5 Al heat sink with a 9000pro, the other Tiger/Leopard, Xserve DP 1.33 Cu heat sink with a 9700pro, I use apple external power supplies for each ADC monitors to reduce load on the internal PSU's. Im trying to keep them running as cool as possible to increase longevity.

Question about PATA IDE connections, I have in both OWC SSD in the ata100 drive bay, i want to keep a HDD in the same bay but connect it to ata66 connector, i have a spare optical drive ata33 cable from another MDD G4, its 24" long so should reach, is this ok, or is there an 18" limit for ata66/100 connections?

Also, i assume its possible to connect additional HDD's to the ata33 albiet slower than ata66.

Im trying to avoid populating the ata66 bay to improve airflow to keep the cpu less than 45°C under load, additionally im considering two 60x60mm fans on the internal intake grill or a 120x120x12mm fan in the base, (id need to cut a hole) in the ata66 bay area.

 

[repairedCheese]

Near as I can tell, the ata33 cable is going to slow down the drive if you use it with the ata66 drive. It doesn't matter what you connect it to, it's just a slower cable, and ata66 standard seems to be backwards compatible. Take that all with massive amount of salt, but I think it would, at least work, just slowly.

Mind you, I haven't seriously dealt with ide in a decade, and I don't think I ever had any computers with both 33 and 66 back in the day, so it never came up. So take that grain of salt and make it a couple pounds of salt.

 

[Eriamjh1138@DAN]

All ATA drives are supposed to be backwards compatible. I don't know about cable length limitations, but shorter is better.

Multiple drives on a single bus (master and slave) basically share the bus, so any simultaneous access reduces their throughput.

I thought MDDs were already running ATA100 busses or even ATA133. Did you confirm via everymac.com what your MDD has in it?

 

[andysa1966]

there are 3 bus available, ata100 to the rear, ata66 in the front bottom and ata33 for the optical drives

 

[andysa1966]

To test, i put a HDD under the ODD in empty bay, using the same ODD ribbon cable, both set to cable select. At the other end on the MB i switched it from the ata33 to the ata66 connector, so 24" cable is working no issues witth the HDD

 

[andysa1966]

I had a failed psu, I took the two 60mm fans and fit them to the intake grille, no cutting, just waiting for two molex to farn adapters to arrive to test.