Cyberstorm mk2 black screen
 

Hi.

I have a Cyberstorm mk2 that I sent to a repair company here in Norway. They checked for bad traces to the edge connector I believe it was, but did not do anything else. Except they also could not get their amiga to boot with it.
The CPU, crystal and power regulator works fine. The cpu gets normal hot.

Do I need to have ram installed in order for it to boot?
Now I am using a cpu without FPU, does that work or do I need the "full" CPU?

Using a microscope I removed some solder blobs that looked like it shorted some pins of a s74fct 543tq 9535 chip and I am wondering if one of them is broken. Is there a datasheet for that chip? I cant find that exact one.

I remember someone saying the CPLD could be broken. What chip is that?

Do you get the coloured bars on the screen when you power on?

I don't think it needs RAM.

Are Clock jumpers set correctly (EXT)?

I don't get any colored bars. Jumpers are set to EXT.

I believe the jumpers have to be set to INT (Internal) for the CS MK2.

For A3000:

J100 = 1-2
J102 = 2-3
J103 = 3-4
J104 = 1-2

For A4000:

J100 = 1-2
J104 = 1-2

I find it a bit confusing, I have read it should be on INT and EXT, but I have tried both ways. It seams logical to me to set it at EXT since it's using it's own crystal that's on the accelerator.

You say you are using a CPU without FPU which suggests it isn't the original CPU.
Is there any chance this was a 68040 model?

Check the jumpers here.
https://bigbookofamigahardware.com/b...ct.aspx?id=263

I got the same card in A4000 and A3000.
The jumpers should be set to INT.

http://megaburken.net/~patrik/CyberstormMK2_en.pdf

I use the full 68060 in the A3660 now.

Ok, I will set the jumpers to INT.

it's the MK3 that needs jumpers set to EXT.

The jumpers are again set to int, but I still only get a black screen.

Any ideas for what I could measure with an oscilloscope?

Hold the phone......

Ram on or off doesn't matter. It works with or without but better with.

These type of edge connectors & CPU PCB's are old & most times, care needs to be observed when installing them....

On the A4kD, there are only three mounting screws down the side of the Mobo.
When you push the Accelerator into this slot, the motherboard naturally bends in between two of the three side fixing's for the motherboard, due to the pressure exerted. This can cause an incomplete connection for some of the contacts. - Try and wedge an Eraser in the middle area of the slot from the side of the motherboard. This will make sure the motherboard doesn't sag & promote a better connection.

With the Drive bay out, you can use your finger tips, but it can hurt when you apply a downward force to push into place. (But only of you're not a True Ami-gan! :P)

When you power on, you're looking for flashing blue horizontal lines on your monitor. (or was that just the Blizzard 1230 MKIV?) - There is a screen notification that the CSMKII has been seen.

If this still doesn't work, try pressing firmly on the CPU & then press the Pwr button whilst keeping the firm pressure on the CPU. If it boots or try's to when you let go, chances are your BGA Socket on the card needs re-balling. - You can check this by turning on normally & then pressing the CAP's Lock key every second. - It should go on-off-on-off for more than 6 times.... If the CAP's Lock Key LED stops responding & you know the CPU is working, then it's definitely time to have your cards BGA socket re-balled.

The CAP's lock key not responding is a known proof test to confirm a CPU issue. :great

But don't exert so much pressure on it that your card collapses & snaps. :nervous

Caps lock key stops responding! I am sure I tried this before and it would always respond. Now I put something under the cpu socket, pressed down on the accelerator and yeah,,black screen and caps lock stops responding.

I have had some issues with keyboard not working and locking up, and caps lock just blinking, even if the computer and mouse works fine. Could bad soldering on the cpu socket or something be the reason for both problems?

The CS MK2 has a through hole CPU socket, so it is not as common for it to have solder joint problems. The CS MK3/PPC is the one with the surface mount PGA socket.

However these are old cards, you never know if it has been damaged and now has some kind of solder joint problem. :-)

ok, so I just reflow the hole card then perhaps :P Too bad there is no schematics available.

I would recommend against that to be honest.

Measure clock signals with an oscilloscope. Start from the oscillator.

:agree ....brittle springs to mind.....

It would appear you did the socket assembly ok & then bummed out with the CAPS light stopping responding. - This is indicative of a CPU fault.

& then you say they keyboard could be dodgey.... :spin

Best get that oscilloscope de-dusted.