68882 question from a n00b

[skote]

Can I stick a 20MHz 68882 into my GVP Jaws board, which has an 030 running at 40Mhz, or will it go p0p? The reason I ask is that I hear they overclock OK...... Will the board just run it at 40Mhz, or do I have to do some jumpery things?

[Hougham]

Don’t read to much in to what I say here. But if no one knows the propper anser it may be worth a read. From what little I know of these you should have no problem. But that is not really Amiga derived and defiantly not GVP jaws derived as I know not what one is. But I have never not had a 82 run at 40mhz even the cheapest and slowest of ones. I have a, well actually I don’t know what the board is anymore. But its in my Amiga and a genuine ceramic packaged MC68030RC40B running at 40Mhz and a cheap and tacky MC68882F…. also running at 40Mhz. The … at the end of the 82 was as they have blatantly just get the cheapest one they could and whacked that in the board and buffed the offending clock rate off. I got that hoppup board band new like that.

[skote]

Hmm.. I noticed on a picture of a Jaws board (GVP 1230+ in case you were wondering) on Amiga-Hardware.com has a 40MHz CPU and a 33MHz 68882 stuffed in it.... I wonder.... Incidentally, SoftHut have these too and have offered me a 33MHz or 40MHz one....

[Zetr0]

@skote

firstly there are only few exceptions when an FPU is required, 3D rendering other math intensive proggys (like Vista FP versions etc)

now that said... theres nothing like the feeling of a fully populated card.... even if you will only use that extra fpu for 5% of the time

Okay... firstly the FPU will over clock nicely, i have read that 25mhz parts running nicely (with a heat sink) at 40mhz. the real heat only comes when its in use and not the 95% when its idle, so as long as you have good airflow it should all be good.

but obviously you take this under you own risk.

I would be happy clocking a 33mhz part at 40mhz, and 25mhz at 33mhz, clocking it at 40mhz would require a nice heat sink me thinks...

now all this talk of heat sinks is fine, but if you are keeping this inside a desktop case, then finding a sink low-profile enough, and obviously airflow could be a problem.

anyway.... this is all hackery.. and hackery is subject to hardware pr0n

[skote]

Heh. Thanks. I have to say that I am something of a closet upgrade freak so a nicely populated board does have a pleasant glow to it. I haven't bought a new FPU yet, but I just might. Mind you... I have just bought an A1500 on eBay so I'll be playing with that... and asking MORE questions of your wise selves....