karlos: yes because of context switching and the fact that we only got a OS thats 68k , and kernels such as warpos and powerup struggles on a 040 25 with a ppc onboard.
sure it depends on the coder in most of the time but not when it comes to general useage, alot of people get dissapointed by the lame? speeds you get on a 040ppc compared to a 060 ppc, sure it helps to clock the 040 to 33 or 40 mhz but then again you could always clock to 060 to 62mhz (best cache/mem speed results) or do an overkill clocking to 80mhz like i did a year ago (slow mem speed but the cpu works faster anyway

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anyway my point is ofcourse mostly targetted at AMIGAOS and its 68k side, since there isnt much ppc games/demos*tools etc to be found so your most likely to sit on the sideline and use a 040 at 25mhz which infact is at many times slower than a 030 50mhz , but this will change as soon as either morphos or os4 is out for bppc or even cspppc (i doubt there is many 040 csppc's left, as its easy to upgrade to 060)...
anyway there is nothing wrong with buying a 040 / 25 card with a ppc on it, but just dont expect it to do miracles oh and dont sell your 060 card to fun it for a 040 ppc just yet, you might regret it alot.
karlos:give me the link to that tool from aminet and i will give u an bppc number (060/240)
cheers