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UDMA locks up windows

spacebrain asked
Medium Priority
Last Modified: 2010-04-27
I installed windows 98 full version on a clean partition. Everything works fine unless i enable the dma setting under hard disk properties, when the computer reboots it seems to work fine but i try to start explorer, it performs an illegal operation and the computer freezes up, no ctrl+alt+del, power switch doesnt work, hard disk led is solid orange and i have to UNPLUG the computer. Bios recognizes the hard disk as udma mode 2 as well as the 32x acer cdrom and the same controller.I updated the MB's bios (Asus P2L97).
My computer:
-Asus MB
-66mhz bus clock
-P2 233mhz
-128M ram
-Seagate medalist pro 9140 ultra ata (primary master)
-acer 32x cdrom (primary slave)
-HP 7200i cdr (secondary master)
-creative dvd-rom (secondary slave)
-pci mpeg decoder board
-agp ati all in wonder pro
-sbawe64 gold
-winmodem 28.8 (x2 drivers installed)
-D-link pci ethernet card
Run win 98 build 4.10.1998
What should the settings be for udma? set bus clock at 83mhz?
Thanks in advance for your help


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Unchain the acer cd-rom. Sorry, cd-rom does not work well with hard drive especially when it is udma.


ok but where im i supposed to put it?

That's the limit.
If you want to use it, then you have to disable udma in the bios so that Win98 will not use the udma driver.
But again, chaining cd-rom to the hard drive will slow down your hard drive.
Why you need two cd-rom's?


i dont want to use a 400$ dvd rom for games or music instead of a 90$ drive... I had a beta version of win98 (roc3 build 1900) wich worked fine with the dma setting on

OK, try change things around. Try the HP or the Creative. Move the Acer to the second controller.

Just don't try enabling DMA setting under Properties, since I haven't been able to tell any performance difference.  Also, the problem isn't with the CD or DVD, I'm running an even stranger config (CD-ROM as master; HD as slave), without any problem.   I'd see if you couldn't get a patch for Win 98, and until then just don't enable the DMA.  


The dma setting does something. I just tested my hd with adaptec easy-cd creator data transfer rate.
small files=2049 KB/s
large files (6 MB+)=3079 KB /s
with the other build of 98 i had 3000 and 6000 rates


btw the setting for udma is auto in the bios and both are detected as udma mode2, the computer runs fine unless i check dma in the properties

Hello space. I have a PII 400 with 2HDD 1 x creative DVD 1 x HP7000i IDE0 = HDD0, IDE1 = DVD, IDE2 = HDD1, IDE3 = HP_CDROM. The settings I have in Win98 are set to UDMA and it all works perfectly and the transfer rate is much higher.

Front Side Bus (FSB) speed has no relevence to the DMA transfer. This is only between the Memory and the processor. Being a PII233 this should be set to 66MHZ with Clock multiplier set to 3.5.

Your HDD will slow down with a CDROM on the same controller only if the CDROM used is of a low standard or quite old, but I doubt you have that problem.

You most likely have a DMA conflict not being shown by WIN98. Look under the \Control panel\System\Device Manager\My Computer - Properties. Check DMA. See what is using what. You should find that LPT1 is using DMA 3, SBAWE64 using DMA 1 and DMA 5, Floppy controller DMA 2, DMA controller DMA 6.

Check to see which WIN98 Hard Disk Controller driver you should use instead of just using the default MS driver. You may find there is a better one for your mother board. Check both Motherboard site and HDD site.

Check with the HDD manufacturer to see that there isn't a conflict with this particular motherboard.

Shrike, you won't see a performance increase if the machine isn't setting it correctly. You may need new drivers. Win95 also doesn't support it correctly if you are using WIN95. Try some analysis to see if there is any difference. Go to WWW.WINBENCH.COM to download winbench. It's the best benchmark around.
mikecrIT Architect/Technology Delivery Manager

What is the illegal operation error that your receiving?



Mike: there is no illegal operations, it just locks right up when i start explorer
durcaj01: yes the dma are as you describe em except that the direct memory acces controller is on dma 4
I tried enabling dma only for the hard disk and it worked so far so i'll see what happens.
I'm sure though that under the other ver of win98 both hard drive and cd-rom where enabled and working properly


ok got fatal error at 023F:BFF9DBA7
i found a driver from acer and the line goes like this in the config.sys file
after booting with this line annd the dma setting under windows i had a 2049 KB/s in the adaptec test but starting explorer still makes the same problem...
without the dma setting i got 2048 KB/s i guess ill just have to live with it unless an expert or me finds a better solution or maybe a microsoft patch....
Hard disk is still enabled and warking properly as of now.

How are the hard drive controllers listed in device manager?


intel pci bus master 82371ab/eb pci bus master ide controller
both controllers at dual fifo


Adjusted points to 200

Have you tried swapping the "primary slave" and "secondary slave" devices,
i.e., recable each of them to be "secondary" on the "other" IDE channel?
Got an IDE port on your sound-card?


there's no ide port on my sb.
I'll swap them and get back to you

Have you ever seen an "Unknown PCI Bridge" or "Unknown PCI Card" device listed in Device Manager?
If so, see:

I don't think your HD controllers are configured correctly. (dual fifo instead of Busmaster child devices)
There is a downloadable PCI Bridge fix for your chipset that may correctly enable proper UDMA support of your devices.
It is available here:

Let me know how it goes, or if you need more.


I tried installing the fix but the setup program told me i didn't need it and then closed
got this error when tryin to start explorer once the dma settin for the cd-rom was enabled:
EXPLORER caused an invalid page fault in
module KERNEL32.DLL at 023f:bff9d709.
EAX=c00300f0 CS=023f EIP=bff9d709 EFLGS=00010212
EBX=005fffbc SS=0247 ESP=005bfeec EBP=005c0188
ECX=00000000 DS=0247 ESI=00000000 FS=415f
EDX=bff76859 ES=0247 EDI=bff79050 GS=0000
Bytes at CS:EIP:
53 8b 15 dc 9c fc bf 56 89 4d e4 57 89 4d dc 89
Stack dump:

does it help anyone?
I think that Ralph hit the nail.  You probably didn't get the right driver for your PCI Bridge.  The problems you desrcibe are all pointing that way.  Who made your system?  You may have to contact them for the correct Win98 drivers for your motherboard, or you may be in need of a bios update.
You can see this same problem popup on someone who got a pentII and tryed to reinstall Win95 on it without getting the PCI Bridge driver first.  Some manufactures send them along n a little pink or yellow envelope, and Gateway puts them on their new E-series CD that ships with all new PC's.  
Also, the order which IRQ's are assigned when installing Win98 on new hardware are very important. Remove all the add-ons and reinstall your Win98, or reconfigure it so the PCI bridge, and video get the correct IRQ's, then add things in this order.
If you leave all that hardware in when you install Win98, then your betting that plug-n-Play will save you, it won't.

1 - UATA or whatever PCI Bridge drivers you have
2 - USB ports if you have them
3 - DirectX if you have it.
4 - Video
5 - Sound board
6 - Modem
7 - Network if you have it.
8 - Printer drivers

Remove the NIC card. It also uses DMA.


i think i how you an apologize and 250 points
the acer is now slave on 2 controller set as udma
so is th hd and for now it works fine (1 week)

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dvd is on the same controller as the hd and the hp is secondary master
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