Quoting the UltraLinux web page (only SMP systems):
The SparcStation 10 and SparcStations 20 are SMP capable machine and according to the FAQABOSS the following combinations are known to work:
And, as stated earlier, CPU modules in SparcStations 10 and can run a different clock speeds, the following ones _SHOULD_ work:
How does it performs? Well, it is fast, really fast. Some of the java Demos can run faster on a dual HyperSparc 125Mhz 128MB ( ywing ) than on a dual celeron BP6 433@433Mhz 192MB ( calimero ). The same applies for the Gimp. When it comes to compiling calimero runs faster than ywing. Both computers running 2.2.16 kernel and calimero's hard disk subsystem is full SCSI.
One important detail when you plan to have different CPU modules in your computer is to have the same kind of modules, you cannot mix SuperSparc and HyperSparc for example, but you can have an odd number of CPUs, for example 3. They are said to be able to run modules at different clock speed as written in this article form AcesHardware , but I have not witnessed it. (Lionel, trollhunter Bouchpan-Lerus-Juery)
(David Miller) There should not be any worries.
The only known problem, and one we don't intend to fix, is that if you build an SMP kernel for 32-bit (ie. non-ultrasparc) systems, this kernel will not work on sun4c systems.