IBM PC desktop with PCI/MCA ?

[65535]

I know there was an IBM desktop model 6886 that had both PCI and MCA slots in it. Anyone have more details on it? Would be an appropriate model to add to my PS/2 collection if I could find one.

 

[PeterNC]

IBM PC 730 & 750. Good luck.

https://en.wikipedia.org/wiki/IBM_PC_Series

 

[njroadfan]

IBM "Select a bus" machines. Neat option, only difference between the ISA and MCA systems is the riser card that contained the bridge chip. The PC Server 520 also sported the feature but with EISA instead of ISA. Just be aware that while Windows 2000 will run on the machine, it will not support MCA cards due to the lack of support for the PCI-to-MCA bridge chip. The ISA and EISA risers should work fine however.

 

[ps2guru]

I still have my IBM PC 750 6886 Select-A-Bus PCI/MCA machine back from my IBM days. It's basically a pseudo MCA bus machine. The planar is PCI and ISA bus with MCA to PCI bus bridge logic on the riser card and a specific BIOS to utilize and configure it. Copies of the reference and diagnostic disk images can be stored in a hidden bootable "convenience partition" on the hard drive just like the later PS/2s that have Sure-Path flash BIOS. The riser card and adapter card slot back plate can be swapped and BIOS reflashed to make the machine PCI/ISA(hence the SelectaBus name.) Early models of the IBM PC Server 310 were also based off the PC 750 computer case and PCI/ISA or PCI/MCA internals.

PC Server 520 was an OEM Micronics design made for IBM. There were two different planars used in PCI/EISA and PCI/MCA variations. Its not what IBM called SelectaBus with a interchangeable bus riser card. Buggy machines that never really got all the kinks worked out before IBM withdrew them from marketing. I purchased a PC Server 720 brand new which was a PCI/MCA bus machine with a separate high-speed bus for the memory and CPUs. It had six Pentium 166MHz processors, 256MB of RAM and a dozen hard drives in a RAID array. Cost a ton of money and was obsolete in a year after IBM completely gave up on MicroChannel.

Last month there was a PC730 PCI/MCA machine on eBay for $99. It was mislabeled as a PC 330 and there was no mention of it being the Microchannel version of PC 700 series desktops other than the pictures showing it was. This is smaller version of the PC 750 with three drive bays and three card slots. I mentioned it on the IBM PS/2 Usenet group and another longtime IBMer bought it up already.

 

[rbarquer]

I still have my IBM PC 750 6886 Select-A-Bus PCI/MCA machine back from my IBM days. It's basically a pseudo MCA bus machine. The planar is PCI and ISA bus with MCA to PCI bus bridge logic on the riser card and a specific BIOS to utilize and configure it. Copies of the reference and diagnostic disk images can be stored in a hidden bootable "convenience partition" on the hard drive just like the later PS/2s that have Sure-Path flash BIOS. The riser card and adapter card slot back plate can be swapped and BIOS reflashed to make the machine PCI/ISA(hence the SelectaBus name.) Early models of the IBM PC Server 310 were also based off the PC 750 computer case and PCI/ISA or PCI/MCA internals.

PC Server 520 was an OEM Micronics design made for IBM. There were two different planars used in PCI/EISA and PCI/MCA variations. Its not what IBM called SelectaBus with a interchangeable bus riser card. Buggy machines that never really got all the kinks worked out before IBM withdrew them from marketing. I purchased a PC Server 720 brand new which was a PCI/MCA bus machine with a separate high-speed bus for the memory and CPUs. It had six Pentium 166MHz processors, 256MB of RAM and a dozen hard drives in a RAID array. Cost a ton of money and was obsolete in a year after IBM completely gave up on MicroChannel.

Last month there was a PC730 PCI/MCA machine on eBay for $99. It was mislabeled as a PC 330 and there was no mention of it being the Microchannel version of PC 700 series desktops other than the pictures showing it was. This is smaller version of the PC 750 with three drive bays and three card slots. I mentioned it on the IBM PS/2 Usenet group and another longtime IBMer bought it up already.

Hi, I have a PC750 6886 with PCI/MCA I am trying to get back working. The computer right now just beeps 1-3-1 when I install the kind of RAM that I have. It came with one SIMM FRU 60G2950 but all it does it beep 1-3-1, I am placing it in bank 1 (the middle one) but not sure it is compatible and if it would work with just one SIMM in the bank. I also tried with two 07H0264 but the same happens. In fact, If the SIMMs are installed or not, the system will always beep 1-3-1. If I install SIMMs from my IBM PC Server 520 PCI/MCA, I get one solid beep non-stop. I managed to find some 73G3135 SIMMS, but I am still waiting for them. I am hoping that once I install those, the system is able to see them. If the motherboard is bad, I wonder if I can use a non-MCA PC750 and load the 6886 bios with the MCA/PCI raiser and make it work. Any ideas on this? Thanks!