Is this an accelerator?

[ruffian]

Is this an accelerator?

I have something like the image at the bottom of this page, except on the one i have there are, iirc, 4 chips arranged horizontally at the top and not 8 as in the image on that site.

http://www.cpu-world.com/CPUs/68030/...8030RC50C.html

Thanks in advance

[DDNI]

yes the 8 chips are a standard 72pin simm. Your 4 chips are simply a different simm (still 72 pin standard though)

[ruffian]

Doh! All i had to do was remove the board, it says its a blizzard on it. What I don't understand is, mine has a chip underneath the processor, in the space on the board on the picture attached, what is this?

No idea if the accelerator works, i tried holding down the L shift Amiga Right Shift Amiga keys on boot up but no option screen appears.

[chiark]

Try left mouse button right mouse button - not sure there's a keyboard shortcut...

The space is for a 68882 floating point unit.

Another Miggy chap in Leeds - hurrah!

[fitzsteve]

The smaller chip below is an FPU, its a maths co-processor.

Its not used in much software but adds some prestige to the board.

Does the Amiga boot into workbench with the accelerator in place?

You should see some 'other' memory on the right hand side of the top bar and also go to workbench:tools/show config and it will tell you what the processor is. Standard Amiga 1200 is 68020 with that card it should show as 68030 and 68882 which is the FPU.

Steve.

[Zetr0]

What you have there is blizzard MkIV 030 @50MHz Accelerator card.

The small Socket beneath the CPU is infact a socket for a PGA based FPU (68881 or 68882) these can range between 25-50MHz

with the CPU card plugged for the most part will be transparent in operation, to know if its working (the fact the machine boots is a plus)

you can hold both mouse buttons down on boot, then once the pre-boot menu appears select adapter cards you should see a manufactures number and a status of Working =)

This card can have upto 128MB of ram onboard, as well as an optional Fast SCSI 2 adapter which also has provision to increase the RAM a further 128MB (max 256MB)

this particular card has a market value between £90 - £130, with the Fast SCSI 2 option this could be closer to the £160 - £200 it depends on the retards on eBay to be honest.

the Blizzard Mk4 030@50mhz is over 9 times faster (in cpu processing terms) than a basic vanilla A1200 (no fast/no accelerator) setup

hope that helps.

[ruffian]

Originally Posted by chiark

Try left mouse button right mouse button - not sure there's a keyboard shortcut...

The space is for a 68882 floating point unit.

Another Miggy chap in Leeds - hurrah!

I have no mouse, figured the kb equivalents would work, obviously not. So what does a floating point unit do?!

Actually, its more like York, though I go to Leeds regularly!

[Zetr0]

in mathematical terms there are two primary constructs of calulation.

whole numbers (integers) and fractions (floating point)

integers, being whole numbers are simple yes/no calulations (look up "two's compliment"), however floating point (fractions) require a lot of work from the CPU in some cases 4 or more times as much work is required to equate a simple floating point sum.

by offloading this work to a specifically designed chipe (an FPU) the calculation of floating point numbers are completed as effciently as integers, as such speeding up calculation time.

all that is done transparently with the FPU co-processors once installed.

it is mainly 3D mathematical vector calculation / scaling etc that hammer the FPU, for the most part 95% of Amiga software doesn't need it.

although... its always nice to have one

[Jope]

Originally Posted by Zetr0

all that is done transparently with the FPU co-processors once installed.

You might want to add here that and as long as the software was written to utilize the FPU.. ;-)

[chiark]

Indeed. "Transparent" it most definitely isn't - you need to have the versions compiled to take advantage of the FPU...

I bought a Blizzard MK IV just a couple of weeks back: great cards.

Unfortunately the kb equivalents don't work for the preboot menu. It is annoying... But as mentioned above, showconfig will do the job of showing you what's in there and whether it's working

I think there's 3 regulars in or around Leeds now (myself and you included!).

[Zetr0]

@jope / chiark

Indeed, transparent was not the best way to put it lol!

[ruffian]

Originally Posted by chiark

Indeed. "Transparent" it most definitely isn't - you need to have the versions compiled to take advantage of the FPU...

I bought a Blizzard MK IV just a couple of weeks back: great cards.

Unfortunately the kb equivalents don't work for the preboot menu. It is annoying... But as mentioned above, showconfig will do the job of showing you what's in there and whether it's working

I think there's 3 regulars in or around Leeds now (myself and you included!).

Thanks, I'll try showconfig then if thats on my workbench 3 disk. Who is the other Leeds area dude then?

[chiark]

Danhans IIRC