I got some strange situation that all my IDE drives can use UltraDMA in the begining, but for unknown reason, one of it can only use PIO mode.

My motherboard's chipset is VIA KM133A and with AMD Athlon 1500+ CPU.
OS is Windows XP Pro.
IDE bus 1 connect with: Maxtor 120GB HDD and BenQ DW1600
IDE bus 2 connect with: Asus E161P DVD-ROM and LiteOn 163S CD-ROM

The UltraDMA become unavailable to one of the drive more than 2 times. One is the Asus DVD-ROM can only using PIO mode. I resolve it by switching it with LiteOn 163S to let Windows XP though there are some new hardware. Then all drives can use UltraDMA.

But not so lucky. Recently, the BenQ DW1600 got the same problem that UltraDMA becomes unavailable. I even install VIA's 4in1 driver which is including IDE Bus Master driver. But not working.

Well..... I can't figure out what's the problem. So, I switch the drive's connected channel again. Now they become:
IDE bus 1 connect with: Maxtor 120GB HDD and Asus E161P DVD-ROM
IDE bus 2 connect with: BenQ DW1600 and LiteOn 163S CD-ROM

Although this resolved my problem, but I don't think this is a good idea. What if it happens again?

Does anyone know the exactly problem is and know how to prevent from it / resolve it?

Thanks.

Have you tried SP2 for XP?

(in reply to arith)

[Deleted by Admins]

(in reply to emperor)

Not yet to try SP2 for WinXP due to the SP2 for TCH is actually not officially released.

I use 80pins cable for IDE bus 1, and use 40pins cable for IDE bus 2 before but already changed to 80 pins cable.

80pins cable is required for my HDD (it support ATA-133), and BenQ's manual also ask user to use ther 80pins cable to connect to the DVD writer.

So, cable may not be the reason.

I heard that many people will guess that's VIA chipset + Windows OS combination's problem. They will say this problem seldom occurs on the machine with Intel's chipset. Though I am not sure about that.

(in reply to Deleted User)

Never had problems with Intel chipset and Windows, with VIA i had sometimes problems enabling DMA

(in reply to arith)

not a good news for me.

(in reply to emperor)

Maybe someone else has better experience with VIA chipsets

(in reply to arith)

quote:

ORIGINAL: emperor

Never had problems with Intel chipset and Windows, with VIA i had sometimes problems enabling DMA

As did I, they are very hasty in that regard/.

(in reply to emperor)

Means the better might be to upgrade my machine with a new motherboard and consider to use other vendor's chipset instead of VIA? (Maybe use SIS chipset?)

(in reply to Clint)

http://www.viaarena.com/?PageID=342 - may be worth installing the non-default MINIPORT version of the driver, as it supports stepwise down-modeing on transfer error.

http://www.viaarena.com/?PageID=340

If you are prepared to bite the bullet and upgrade the RAM to DDR as well, but you may want to wait and see how 64 bit plays out.

I think I like the Sis chipset - I'd describe it as having neither vices nor virtues, and the drivers seem to be more solid than either VIA or Nvidia.

(in reply to arith)