14 December 2009, 19:09 | #1 |
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Overclocking 68882
Is there a real benefit of overclocking the 68882? I have a 50mhz 030 board and the 68882 actually overclocks and works fine up to 66mhz(via changing crytals). What programs use the co proc? is it really worth overclocking?
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14 December 2009, 19:19 | #3 |
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Depends what you're doing with your FPU. If you're running a ray-tracer or something then maybe.
Almost nothing uses the 68882 FPU. No games. Very little workbench software. Unless you're running a ray-tracer then it is hardly worth even having it on your accelerator. It just eats electricity and puts out heat. |
14 December 2009, 19:31 | #4 |
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You'd better overclocking a Microwave to 3000w. That way you can have your McCain microchips in 1 second flat
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14 December 2009, 19:36 | #5 |
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14 December 2009, 19:38 | #6 |
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Any application that uses floating point math using AOS's standard math libraries can use the FPU when you replace those libraries with the FPU versions that you can find on Aminet. I haven't tried those replacement libraries, because I don't have an FPU, but people who do may want to give those libraries a go.
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14 December 2009, 20:00 | #7 |
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Good point, Thorham!
I noticed, when I was contributing to the mpega.library (WarpUP) problem thread, that the MPEG Audio decoder V2.4 libraries comprise FPU versions as well, so the FPU may also be useful for playing MPEG files. |
14 December 2009, 21:48 | #8 | |
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Quote:
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14 December 2009, 21:55 | #9 | |
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Quote:
The FPU is nice to have but like previously said not much uses it. |
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14 December 2009, 22:04 | #10 | ||
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Quote:
Quote:
Last edited by alexh; 14 December 2009 at 22:10. |
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14 December 2009, 22:11 | #11 |
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14 December 2009, 22:19 | #12 | |
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It was not MPEGA.LIBRARY it was just MPEGA but I'm 80-90% certain I would have been using the correct optimised version for the A3000 if there was one.
It couldn't decode mono 128Kbit fixed bit-rate MP3's at 22KHz in real time. This was a long time ago, maybe 12 years ago (1997/98), but I doubt MPEGA has been optimised much in all these years? mpega020FPU.library (which is not what I used) is described by the author as potentially slower than MPEGA and it's code has not been touched in 10 years. But as I said, it was not what I used. EDIT: After reading a bit I think MPEGA is fixed point only. But you have to take into consideration what the author of MPEGA.library says Quote:
Last edited by alexh; 14 December 2009 at 22:30. |
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14 December 2009, 22:28 | #13 | |
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The lack of any distinct advantage to be gained by most users makes you wonder why provision for the FPU was a relatively common feature of Amiga accelerator cards. And that makes you wonder why he bothered, unless it was just proof of concept! |
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14 December 2009, 22:34 | #14 | |
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The standard Amiga math libraries are strictly floating point. |
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14 December 2009, 22:37 | #15 |
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I wouldn't say deplorable. Just unusable.
This tool is pretty much a try once and never use again tool. (At least for me) Which I think is like most of the other FPU enabled programs. I'm still open minded to hearing about a bit of software (one we all use all the time) which benefits from the FPU. Perhaps one we just didn't realise uses it. The odd demo when you run it says "FPU required" and doesn't load. And these are times you wished you had an FPU. I know because my A4000 originally had an LC040 with no FPU. However when you look closer, most of these demos are marked "060 recommended" and suck on anything less. As I found out when I got my full 040 Last edited by alexh; 14 December 2009 at 22:44. |
16 December 2009, 20:47 | #16 | |
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Quote:
OK, it puts more complexity when designing the physical board (routing) and require at least four layers. But all Amiga accelerators have four layers. |
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16 December 2009, 21:08 | #17 |
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Yes, that would explain it. Thanks for clearing that up.
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