Picasso IV display issue

[nashio]

Hi all.

Looking for some advice/assistance. I've revitalised my A4000D, and in the process I've added in my old Picasso IV card. It is fitted to the bottom-most slot (aligning with the A4K video slot) and its integrated flicker fixer which has been separated from the main board (since the time it was used with my old A2K) is fitted to the inline video slot and attached to the PIV via its original ribbon cables... so far, all appears to be working well... however:
 
It's displaying RTG screens fine through its  VGA socket on my Thinkvision LCD (1152x980 res, unfortunately other resolutions are out of range for my monitor it appears).

However I'm having issues when I switch screen modes to any of the native Amiga modes (eg Pal or NTSC low-, high- or interlaced high-res modes).

The resultant output via the PIV's VGA has a decidedly "green" flavour, and also displays distinct vertical "bars" on the screen.

The native modes display fine on my 1084 monitor which is concurrently connected to the A4K's 23 pin RGB output. Obviously I would like all modes to work correctly (if possible) via the PIV's VGA output.

I've attached some images showing the "faulty" native mode output via VGA , the equivalent 1084 display (pardon the shadowing caused by the photography, the output here is perfect, even if the photo isn't), and thirdly the VGA output in all its 1152x980 24 bit glory!

Any advice or help here would be much appreciated.

The A4K is a 68040 with 128Mb of Z3 ram +2Mb chip and no onboard fast ram simms...

[Boing-ball]

Try pushing down on the chips that are socketed. Failing that it may need recapping (Replacement Caps).

[zipper]

Try pushing down on the chips that are socketed. Failing that it may need recapping (Replacement Caps).

p
My opinion, too. One of them is the FliFi chip.

[Boing-ball]

Or even a RAM fault issue… 👍🏻

[nashio]

Thanks guys, I'll try re-seating the chips as a first resort. I would've thought though if that or faulty ram was the issue, it would affect PIV output modes as well?

[Boing-ball]

As far as I can see. The Native modes run through the small interface board which sends the signal through to the Main PIV board for output via the main VGA connector. So can only surmise that some logic is being used on the PIV to aid output of standard Amiga Modes.

Where as on a Cybervision 64/3D scandoubler/flickerfixer board the flicker board is actually acting as a Output bridge

[zipper]

The native modes can be flicker fixed up to 120 / 150 Hz by using software to tweak and flash the board. But also 50 / 60 Hz may be chosen during the boot time.