Apollo 1230 crash with FPU?

[TCMSLP]

Hi All,

I have an Apollo 1230 Mk2 with a 68030 clocked at 50MHz.  When fitting FPUs the A1200 refuses to boot.  The first FPU was rated at 33MHz;  I thought this may be the issue and as I lack any spare crystals (to underclock the CPU) I bought a second FPU rated at 40MHz (the fasted I could find).  Fitting this FPU also results in a fail to boot.

I seem to recall both FPUs resulted in either a constant grey screen, or alternating grey/white with random power LED flashing.  

I'd have expected the 40MHz FPU to at least work, even if it later failed under load.

Both FPUs (one from ebay, one from amibay) were apparently 'tested and working'.

Am I most likely looking at two unlucky (faulty) purchases or is the problem likely to be due to the speed ratings/clock?   The other possibility is the Apollo being faulty

I'm hoping someone has experienced similar and can point me in the right direction!

Edit: I should add, I believe the FPUs are both MC68882FNxx PLCC types.  

Thanks,


Steve

[amiman99]

I have similar problem with mine FPU that I got from Ebay. Works fine at 25MHz, flaky at 33MHz and no boot at 40MHz. The PLCC FPU is rated at 40MHz.
I'm using it on my A3000 with A3630 CPU card.

I did not find solution to that problem, I'm not sure if the FPU is marked improperly or the A3630 card does not work at speeds higher then 25MHz.

[paul1981]

Hi All,

I have an Apollo 1230 Mk2 with a 68030 clocked at 50MHz.  When fitting FPUs the A1200 refuses to boot.  The first FPU was rated at 33MHz;  I thought this may be the issue and as I lack any spare crystals (to underclock the CPU) I bought a second FPU rated at 40MHz (the fasted I could find).  Fitting this FPU also results in a fail to boot.

I seem to recall both FPUs resulted in either a constant grey screen, or alternating grey/white with random power LED flashing.  

I'd have expected the 40MHz FPU to at least work, even if it later failed under load.

Both FPUs (one from ebay, one from amibay) were apparently 'tested and working'.

Am I most likely looking at two unlucky (faulty) purchases or is the problem likely to be due to the speed ratings/clock?   The other possibility is the Apollo being faulty

I'm hoping someone has experienced similar and can point me in the right direction!

Edit: I should add, I believe the FPUs are both MC68882FNxx PLCC types.  

Thanks,


Steve

I used to have one of these cards (mine was 40MHz) and I gave it away due to instability. I should have tried it with the FPU removed, or even a new oscillator...it probably would have worked. Maybe some kind fellow on here will test both of your FPU's for you so that they can be ruled out?

[freqmax]

Shoddy PCB and sockets ?

[bbond007]

I don't know about Apollo(I have never seen any of those boards first hand), but I have seen some other 030 boards brands with a jumper wire soldered to the back of the FPU. I had e-matrix that came this way and I was trying to find out its purpose when I stumbled upon a thread where someone was talking about solving FPU instability issues on yet another brand of accelerator.

[NovaCoder]

The thing is that it's kind of pointless having an FPU with an 030 anyway, there isn't much you'll be able to do with it unfortunately.

[amiman99]

The thing is that it's kind of pointless having an FPU with an 030 anyway, there isn't much you'll be able to do with it unfortunately.

I did a little experiment with Vista Pro trying to render a scene, and there was a decreased render time when rendering using the FPU, so if your FPU is clocked higher then the CPU, then there is a significant advantage by using it.

[NovaCoder]

I did a little experiment with Vista Pro trying to render a scene, and there was a decreased render time when rendering using the FPU, so if your FPU is clocked higher then the CPU, then there is a significant advantage by using it.

Not many people are into 3D rendering with an 030.

[TCMSLP]

Thanks all.  If anyone could test my FPUs I'll happily pop them in the post.

I've noticed some utilities I've installed have come with FPU versions (AmigaAmp comes to mind, possibly some datatypes too?) so figured the FPU would perhaps make a difference.

However, if the difference is minimal I may just forget about it and later look for an '040 card.


Steve