PC Engines support forum

Hello,

until now I used a dozen of Alix6 with both CF and ide hdd and I am quiet happy of this system, anyway I never enabled Udma mode, so I ask you people if there is any downside on enabling it. On alix doc I read 'use at your own risk' so what kind of risk? All CF I used report to support Ultra DMA mode 0-5(4 as default) http://shop.varia-store.com/product_info.php?info=p832_1-GB-Transcend-Industrial-CompactFlash-Card-TS1GCF200I.html and hdd are pata WD Scorpio Blue wich are Udma 5.

If there's no downside in my environment what is the expected speed improvment?

Thanks in advance 

As far as my experience tells me, yes, there are downsides, but that is just IMHO.

For example, I just realized my Ubuntu server 10.4.4 LTS i386 CD is not faulty, but UltraATA and UDMA enabled produces error during calculation of  MD5 checksum. As I write this, jumper on my Alix1 is in  UATA disabled, and autodetection of UDMA is off in BIOS and CR-ROM checksum is going just fine.

CF cards are also made different, and your mileage may vary.