ultra dma mode 2, 3,4,5? wat the difference

[jakol]

got my new harddrives at my home pc, both running on Ultra DMA mode 2? my comp at work on Ultra DMA mode 5? wat the difference? mode 5 i guess has a faster transfer rate? i dont know , anyone could explain this, i did google search but its confusing...ty

[redwudz]

I attempted to dig through the PIO-DMA info also. I'll leave it to others to clarify the differences.

Simply put, my CD and DVD drive are Ultra DMA 2. (33 or 66MB/S as far as I can gather)

My Harddrives are Ultra DMA 5. (100 or 133MB/S)

Bottom line, if your HD is running at Ultra DMA 2, you have a problem.

As far as how to fix this, a few suggestions.

Make sure you have a 80 conductor cable for your HD's. These will also work with slower devices such as CD drives, although you would not see any speed increase with the slower devices.

With XP, make sure DMA if available is selected in your Device Manager for the drive channel you are using.

If you have done all this, then maybe others can make some suggestions.

[gitreel]

Check out this link

http://www.pcguide.com/ref/hdd/if/ide/modesUDMA-c.html

[jakol]

thanks for the replies,
on gitrell link, ive read that one, im still trying to figure out why its running on ultra mode 2, im using 80 pin cable, DMA is selected in my Device Manager for the drive channel im using. im sure its running on u mode 5 before i install additional hard drive yesterday, i have trouble installing the harddrive,i booted like 8 x yesterday, bought a 250 gig drive but xp sp1 could not recognize 250gig, only 137gig...dont know why.. i have xp sp1 ended installing 120 gig... anyway its maybe the cause of this, ill try to check BIOS when i get home.

[jakol]

read this one fro maxtor website.
ill try this fix when i get home.


Problem:
The drive controller is set to use "DMA if available" but reports to be only in PIO mode. User cannot turn on DMA for ATA device. The only option for the user who wants to enable DMA mode is to uninstall and reinstall the affected channel, "Primary IDE Channel" or "Secondary IDE Channel". Reboot the system and Windows XP will reinstall the driver for the channel.

Cause:
Windows XP will turn off DMA mode for a device after encountering certain errors during data transfer operations. If more that six DMA transfer timeouts occur, Windows will turn off DMA and use only PIO mode on that device.

Windows XP downgrades the Ultra DMA transfer mode after receiving more than six CRC errors. Whenever possible, the operating system will step down one UDMA mode at a time (from UDMA mode 4 to UDMA mode 3, and so on).

All CRC and timeout errors are logged in the system event log. These types of errors could be caused by improper mounting or improper cabling (for example, 40-pin instead of 80-pin cable). Or such errors could indicate imminent hardware failure, for example, in a hard drive or chipset.

[gitreel]

Try uninstalling the ide channel in the device manager and reboot. When you reboot, the channel will be redetected and hopefully fixed.

[jakol]

thanks gitrell,
thats wat i did,uninstall both ide channel, and rebooted =fix...both on ultra mode 5 now.