i'm wondering if Slackware has support for RAID ATA 100 dual channel and if yes how it's do it.
I'm not sure about a RAID setup. I use a promise ATA 100 HDD, that I have working under Slackware. Check your kernel config. There should be some options for RAID, as well as ATA support. See if any of those match what you're after.
AMD Athlon 2200+ 1.8Ghz
1280MB PC-3200 CAS2.5 RAM
ATI Radeon 9600 Pro 128MB AGP
Western Digital WDC WD2500JB-00FUA0 250GB 7200 rpm ATA/133
Seagate ST3200822A 200GB 7200 rpm ATA/133
Western Digital WDC WD1200BB-00CAA1 120GB 7200 rpm ATA/133
Western Digital WDC WD800BB-00CAA1 80GB 7200 rpm ATA/133
Maxtor OneTouch 2HA43R32 1TB 7200 rpm USB 2.0
D-Link DFE-530TX+ 10/100 NIC
D-Link DWL-G520 Rev.A
Debian 5.0r1 Lenny