Epson Stylus PHOTO 950 User Manual page 278

Note:
If your printer is connected to LPT1, only the LPT1 tab is available.
The available settings are as follows:
Resource settings (IRQ and DMA)
If you have connected your printer to LPT2 or LPT3, making IRQ
and DMA settings here may speed up printing. Click Change
setting and input the same configuration numbers for IRQ and
DMA which you have made with your expansion board. See your
computer documentation to determine the settings for IRQ and
DMA.
Use DMA transfer
Using DMA transfer to send print data to the computer may help
speed up printing. If the Use DMA Transfer check box is not
enabled, you must first enable DMA transfer in your computer
settings. For details, see your computer documentation.
269
Increasing the Print Speed