Should DMA be enabled for an IDE/USB/FireWire recorder?

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Some peripherals require data to be transferred between themselves and the memory at the fastest possible speed. On a computer these are usually the devices handling bulk data such as network cards, scanners, sound boards, video cameras, hard disks.

Usually all data has to be passed through the CPU, which ties up the computer's processing power and slows it down. The solution to this problem is a technique called DMA - direct memory access.

DMA is a method where data is transferred directly from memory to a device without the intervention of the CPU. If the device can take direct control of the bus, this process is called bus mastering.

In theory having DMA enabled allows for better data transfer rate to the recorder, which in turn should allow you to record at higher speeds.

In practice however, not all drives function correctly with DMA enabled. The problems can include "Drive Not Ready" errors when attempting to record, system locks up completely during recording, system crashes when starting GEAR with an "IRQ_NOT_LESS_THAN_EQUAL" error in HAL.DLL, .

If you are experiencing this type of behavior while and all other attempts at remedying the situation have failed, disabling DMA for the recorder may solve the problem.

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