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Roscoe
10-03-2009, 02:16 PM
When my PC boots it has a few (DOS?) screens that gives much information concerning the PC. One such message says:

Pri Master: 8.01 ST380011A Ultra DMA Mode-2, S.M.A.R.T. Capable but disabled
Pri Slave: 3.54 Ditto

What is Ultra DMA and what advantage would it be if it was enabled? If there is an advantage, how would I go about enabling it?

:thanks

Speedy Gonzales
10-03-2009, 02:30 PM
Thats the post screen. Thats showing the hdd and whether smart is enabled

It'll get its info from the BIOS (the option to disable/enable SMART), maybe in the BIOS if it supports it

ULTRA DMA is usually enabled on cds and hdd's, and its usually (I've never seen Mode 2), 4 to 6

utopian201
10-03-2009, 05:28 PM
Ultra DMA reduces CPU usage when the drive is accessed. You can enable it in the bios, and you also have to enable it in windows. Under device manager/hard drive/ under one of the tabs you can set DMA to auto and it should automatically go to the highest one.

Agent_24
10-03-2009, 11:52 PM
Because it says "Ultra DMA Mode-2" it means your drive is using UDMA (Ultra Direct Memory Access) which allows the drive to transfer data directly to memory and bypass the CPU, therefore allowing it to transfer faster and to use less CPU time.

What it's saying you're NOT using is SMART (self monitoring and reporting technology) which is a technology implemented in hard drives to monitor certain properties (like temperature) and to try and give you an advanced warning if it thinks your drive may fail soon.

To enable SMART you will need to go into your BIOS setup and turn it on from there. This then allows the BIOS to check the drives on startup for any problems.

However, even without SMART enabled in BIOS, you can still access the information in windows with a program like SpeedFan

PaulD
11-03-2009, 08:16 AM
ULTRA DMA is usually enabled on cds and hdd's, and its usually (I've never seen Mode 2), 4 to 6

Anything not using an 80 wire connector is limited to Mode 2.

Roscoe
15-03-2009, 07:29 PM
Thank you, gentlemen.

Agent24: I have enabled the SMART in the BIOS and will take your word that it is improving things. It now says 'capable and enabled.' I don't notice any difference, but it does seem that if it uses less CPU time then that must be a good thing.

Paul: The PC originally ran 98 (but now XP) so that would date the CPU I imagine. Not that I am worried - it is doing the job that I require.

Sorry that I have been a bit slow in replying - I have had a long weekend away.:thanks

Speedy Gonzales
15-03-2009, 07:36 PM
Anything not using an 80 wire connector is limited to Mode 2.

Good point