From my notes on the Turbo601 board:
DayStar's Turbo 601 accelerator was designed for "any" Mac with a logic board with a IIci cache slot (IIci, IIvx, IIvi, Performa 600). The IIsi with a suitable PDS slot adapter was also supported.
The Turbo 601 was sold at two speeds, 66MHz and 100MHz. According to Low End Mac, different part numbers were assigned to the three variants of the board (IIci, IIsi and IIvx/IIvi/Performa 600). Unfortunately, the variants are not visually identifiable -- there are no labels that state "This is a IIci board" or "This is a IIvx/IIvi/Performa 600 board". User reports indicate why separate part numbers existed.
The IIsi Turbo 601 requires a PDS slot adapter; a separate part number to identify it from the IIci version is thus evident. When the first cards shipped, users identified that the IIvx family could only use 256 colours (even when VRAM supported more colours in 68030 mode) and built-in sound was corrupted. DayStar offered a "return to base" fix for the IIvx family, installing modified ROMs and shipping updated system software. The fix corrected the video problem, but DayStar never cracked the sound problems. Shortly afterwards, DayStar stopped selling IIvx family accelerators.
Other known problems include high temperatures when used in a IIsi and floppy disk timing problems with some versions of System 7.5. Apple did not sell a Turbo 601 equivalent and the Turbo 601 was not supported by Apple after Mac OS 7.6.1. Unofficial instructions for installing Mac OS 8.0 and 8.1 are available on the internet. The card can be managed using Apple's "601 Processor Upgrade" control panel or by using the more advanced DayStar software. DayStar's control panel is recommended.
The first Turbo 601 that I obtained came from a IIvx but I happily used it in a IIci, so if you come across any Turbo 601, I suggest trying it in any suitable Mac II. Overclocking is possible, but given the relative rarity of these cards, it should be approached with care. Alas, there are no confirmed reports about running a Turbo 601 in an SE/30.
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The IIcx is not mentioned anywhere in DayStar's documentation. It may work if installed in a IIcx with the special adapter board (68030 cpu to IIci cache slot) that DayStar made. A 32 bit clean ROM (from the IIsi or IIfx) may also be required.