1024x768 31khz AGA.. is it possible???

[DamageX]

The pixel clock is number of pixels (horizontal resolution + horizontal retrace) * number of lines (displayed lines + vertical retrace) * refresh rate. For example, NTSC low res is: (320+135)*(200+62)*60=7.16MHz
The Amiga has three possibilities low res, high res, super-high res (28.6MHz NTSC, 28.3MHz PAL)

720x480x60hz or 720x512x50hz plus a bit of overscan is about as good as it gets without interlacing. As previously mentioned, you can get 800x600x70hz interlaced on a 24KHz monitor and the flicker probably isn't too bad (at least compared to a 15KHz monitor).

Since AGA can do 8 bitplanes in super-high res (with 64-bit aligned fetches) it can do it in any possible resolution, but CPU-chipmem bandwidth gets progressively slower going beyond 4 bitplanes in super-high res

[platon42]

@DamageX:

> you can get 800x600x70hz interlaced

Yup. When I could not use my CV64 (Zorro III problem), I used a 912x612x72hz (overscan) mode with a flicker fixer on a (I think) 64 colours workbench. Speed was "okay" (I wouldn't go back though).

Now I'm at 1280x1024x16 Bit at 50 Hz (TFT) with a pixelclock of about 90 MHz, which is the highest the CV64 can do (with CGX, P96 couldn't go right up there).

[Zac67]

The pixel clocks are derived from chipset clock (28.x MHz as DamageX wrote):
Lores: 1/4
Hires: 1/2
SHires: 1/1

A scan doubler could - in theory - double that, depening on which screenmodes is is compatible with. Is there such a thing as a full multiscan scan doubler?

[AmiBiL0]

Thank you all for the reply.

Here what I have found on Aminet

first is the hacked one as someone else has mentioned HighGFX
the next one is WBHacksAGA
I don't know how they do that and if there is a way to change the frequence.

As someone was asking in one of the post, I can change the size in the resolution but not the view size. When I change the default size then the monitor has a large screen but I can only scroll from one side to the other. It doesn't really change the view size. If I am doing something wrong then let me know what to change thanx.

Just for a note I am using WB 3.1. Is this a limitation to actually change the view size? I am planning to go to 3.9 soon. I just got my 3.1 ROM

Thanx again to all for all the info provided till now

BiL0

[Karlos]

To be honest, 1024x768 under AGA is possible provided you don't mind awkward, possibly monitor damaging settings, eyebleedingly slow refresh rates and having no spare cycles left to the Chip RAM for the CPU to actually render anything.

I used to try stuff like this all the time and it honestly isn't worth it. I ended up using 1280x1024x16 autoscrolling on a 640x512 display with a flicker hack called MagicTV for a while, but did the sensible thing and got a graphics card.

[AmiBiL0]

)  I think you're right.
I would love to have a nice video card. Especially as I don't really use much of games etc, but still I don't have enough money to get the mediator or the PPC BV.

As I use the amiga for transfer ADFs and I am in a process of backing up all my original games, then I though if it was easy to have a better or larger res then it would make the work more enjoyable.

If not then I will have to stay with 640x480 VGA

BiL0

[Ratte]

Take a look at:
http://aminet.net/util/wb/MPP.lha

And yes, HighGFX works with filckerfixers.
Tested on an A4000 with CompServAGA FF 2.0.

BR
Andre