Yes, it won’t be quite as fast as the SE/30. Maybe 3/4 as fast.
Theoretically (i.e. at peak), 68030 is a lot faster than 68000. Ignoring the difference in MHz, ‘030 can execute an instruction in just two clock cycles as opposed to four for the 68000. ‘030 can also work with 32 bits of data at once, as opposed to 16. The peak performance of a 68030 is up to 4x faster than a 68000 at the same speed, and of course the SE/30 has twice the clock speed of the SE and doesn't suffer from bandwidth degradation due to "vampire video" as the does the SE. So in theory the SE/30 could be more than 8x faster than the SE. In reality 68030 is complex and doesn't achieve its peak performance as often as 68000 achieves its peak performance. 68030 has more things that have to go correctly in order to achieve the peak speed (L1 cache, instruction overlapping, etc.), whereas 68000 basically achieves peak performance whenever you hook it up to a sufficiently fast RAM system.
Here are some speed figures comparing the Mac SE, Mac SE with WarpSE accelerator, and the SE/30:
Spec | Mac SE | WarpSE | Mac SE/30 |
---|
Clock speed | 7.8336 MHz | 25 MHz | 15.6672 MHz |
Peak MIPS | 1.96 MIPS | 6.25 MIPS | 7.83 MIPS |
ROM bandwidth | 3.92 MB/sec | 12.5 MB/sec | 15.6672 MB/sec |
RAM bandwidth | 3.27 MB/sec | 12.5 MB/sec | 15.6672 MB/sec |
Video RAM bandwidth | 3.27 MB/sec | 3.27 MB/sec | 3.92 MB/sec |
So yeah, 3x faster than the SE in most measures but not quite as fast as the SE/30.
Also, notice how the SE/30’s VRAM bandwidth is not so good compared to its RAM bandwidth. Since the SE/30’s clock is twice as fast, they cut the VRAM width down to 8 bits from 16, as opposed to doubling it to 32 like they did for the regular RAM. So the VRAM speed is basically unchanged from the SE.
One thing not captured in the table is that when the SE/30 writes a longword (32 bit quantity) to VRAM, the processor bus is occupied for 16 clock cycles (1021 nanoseconds @ 15.6672 MHz) and the 68030 can only continue executing if the requisite data is in its rather small 256+256 byte L1 cache. On the WarpSE, this same operation occupies the fast bus for only 320 nanoseconds, some 3x faster. After that, because of the longword posted write buffer, the MC68k on the WarpSE can continue executing from any of the onboard fast RAM or fast ROM at full speed unless another write to video memory occurs before the first one has finished trickling out of the posted write buffer to the RAM on the SE PDS. So although the SE/30's L1 cache is a bit faster than the WarpSE's fast RAM, the fast RAM is way bigger and thus "shields" the processor from slow bus activity more effectively in some cases.