I have loaded Mandrake 10 Official (PowerPack) on a DELL GX270 with a BIOS updated to REV A04. so far so good.

My problem is, that when I add a PRO/100 S Dual Port Adapter , while Mandrake goes thru all the right motions and installs the driver and setsup the ifcfg file, not only does the Pro/100 fail to work but it also stops the internal port from working as well.

The Intel site states that I should use their e100 driver in place of the standard eepro100 driver , but I can install this same card in a non DELL pc without any problems.

Dmesg gives the following output, eth0 is the internal port eth1/2 are the PRO/100 ports
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Intel(R) PRO/1000 Network Driver - version 5.2.30.1-k2
Copyright (c) 1999-2004 Intel Corporation.
eth0: Intel(R) PRO/1000 Network Connection
eepro100.c:v1.09j-t 9/29/99 Donald Becker
eepro100.c: $Revision: 1.36 $ 2000/11/17 Modified by Andrey V. Savochkin <saw@saw.sw.com.sg> and others
eth1: 0000:02:04.0, 00:02:B3:EE:BF:AA, IRQ 16.
Board assembly a56831-004, Physical connectors present: RJ45
Primary interface chip i82555 PHY #1.
Secondary interface chip i82555.
General self-test: passed.
Serial sub-system self-test: passed.
Internal registers self-test: passed.
ROM checksum self-test: passed (0xb874c1d3).
eth2: 0000:02:05.0, 00:02:B3:EE:BF:AB, IRQ 17.
Board assembly a56831-004, Physical connectors present: RJ45
Primary interface chip i82555 PHY #1.
Secondary interface chip i82555.
General self-test: passed.
Serial sub-system self-test: passed.
Internal registers self-test: passed.
ROM checksum self-test: passed (0xb874c1d3).
ip_tables: (C) 2000-2002 Netfilter core team
ip_conntrack version 2.1 (4027 buckets, 32216 max) - 300 bytes per conntrack
inserting floppy driver for 2.6.3-7mdk
Floppy drive(s): fd0 is 1.44M
FDC 0 is a post-1991 82077
hdc: ATAPI 48X DVD-ROM drive, 256kB Cache, UDMA(33)
Uniform CD-ROM driver Revision: 3.20
hdd: ATAPI 16X CD-ROM CD-R/RW drive, 2048kB Cache, UDMA(33)
ide-floppy driver 0.99.newide
NET: Registered protocol family 17
e1000: eth0 NIC Link is Up 10 Mbps Half Duplex
PCI: Setting latency timer of device 0000:00:1f.5 to 64
intel8x0_measure_ac97_clock: measured 49602 usecs
intel8x0: clocking to 48000
irq 17: nobody cared!
Call Trace:
[<c010d543>] __report_bad_irq+0x23/0x80
[<c010d638>] note_interrupt+0x78/0xa0
[<c010d839>] do_IRQ+0xd9/0x100
[<c010bf28>] common_interrupt+0x18/0x20

handlers:
[<e0bb6740>] (0xe0bb6740)
Disabling IRQ #17
NET: Registered protocol family 10
Disabled Privacy Extensions on device c035fe60(lo)
IPv6 over IPv4 tunneling driver
parport0: PC-style at 0x378 (0x778) [PCSPP,TRISTATE]
parport0: irq 7 detected
parport0: cpp_daisy: aa5500ff(98)
parport0: assign_addrs: aa5500ff(98)
parport0: Printer, Canon BJC-210
lp0: using parport0 (polling).
lp0: console ready
Installing knfsd (copyright (C) 1996
bootsplash 3.1.4-2004/02/19: looking for picture.... found (800x600, 11943 bytes, v3).
bootsplash: status on console 0 changed to on
bootsplash 3.1.4-2004/02/19: looking for picture.... found (800x600, 11943 bytes, v3).
bootsplash: status on console 1 changed to on
bootsplash 3.1.4-2004/02/19: looking for picture.... found (800x600, 11943 bytes, v3).
bootsplash: status on console 2 changed to on
bootsplash 3.1.4-2004/02/19: looking for picture.... found (800x600, 11943 bytes, v3).
bootsplash: status on console 3 changed to on
bootsplash 3.1.4-2004/02/19: looking for picture.... found (800x600, 11943 bytes, v3).
bootsplash: status on console 4 changed to on
bootsplash 3.1.4-2004/02/19: looking for picture.... found (800x600, 11943 bytes, v3).
bootsplash: status on console 5 changed to on
eth0: no IPv6 routers present
eth1: no IPv6 routers present

Lspci

00:00.0 Host bridge: Intel Corp. 82865G/PE/P Processor to I/O Controller (rev 02)
00:02.0 VGA compatible controller: Intel Corp. 82865G Integrated Graphics Device (rev 02)
00:1d.0 USB Controller: Intel Corp. 82801EB USB (rev 02)
00:1d.1 USB Controller: Intel Corp. 82801EB USB (rev 02)
00:1d.2 USB Controller: Intel Corp. 82801EB USB (rev 02)
00:1d.3 USB Controller: Intel Corp. 82801EB USB (rev 02)
00:1d.7 USB Controller: Intel Corp. 82801EB USB2 (rev 02)
00:1e.0 PCI bridge: Intel Corp. 82801BA/CA/DB/EB PCI Bridge (rev c2)
00:1f.0 ISA bridge: Intel Corp. 82801EB LPC Interface Controller (rev 02)
00:1f.1 IDE interface: Intel Corp. 82801EB Ultra ATA Storage Controller (rev 02)
00:1f.2 IDE interface: Intel Corp. 82801EB Ultra ATA Storage Controller (rev 02)
00:1f.3 SMBus: Intel Corp. 82801EB SMBus Controller (rev 02)
00:1f.5 Multimedia audio controller: Intel Corp. 82801EB AC'97 Audio Controller (rev 02)
01:08.0 PCI bridge: Intel Corp. 21154 PCI-to-PCI Bridge
01:0c.0 Ethernet controller: Intel Corp. 82540EM Gigabit Ethernet Controller (rev 02)
02:04.0 Ethernet controller: Intel Corp. 82557/8/9 [Ethernet Pro 100] (rev 0d)
02:05.0 Ethernet controller: Intel Corp. 82557/8/9 [Ethernet Pro 100] (rev 0d)

I can answer my own question.
To get this to work simply add "noapic nolapic" to the boot line in GRUB or when doing the installation click on the boxes next to "Force no APIC" and "Force no Local APIC".
Everything else is straight out of the box