That's a Cirrus Logic GD5430 VGA chip. It generally has two settings that can be made by jumper:

- IRQ for VGA (2/9) enable/disable
- Wait states on VLB 0/1

Your problem sounds more like an issue in the analog signal path, neither of these jumpers are likely to change actual image quality.

Just a check though: what speed are you running VLB at? If it's over 33MHz you should consider adding that wait state. To see if that would make any difference, reduce VLB speed to 33MHz and see if that changes anything.

that did it. works ok now