NEED HELP BAD! VGA problem

[Steve713]

Someone please help!

I purchased a dual 877 powermac g4 to use with my old VGA monitors I had from my PC. I heard it was simple to connect using the adapter that comes with the computer. Well, everything fit great, but when I boot up my computer I get nothing. My monitor tells me it can't read the signal for the computer. Well I tried 3 VGA monitor I had and NOTHING! At one point I did get a picture, with an unreadable red tint to it. Why can't my g4 read these VGA monitors????

Steve

 

[Sun Baked]

Strange, especially if you checked the old VGA monitors refresh rate and resolution to as set the video card up to drive the monitor using something that would work.

 

[mklos]

Someone please help!

I purchased a dual 877 powermac g4 to use with my old VGA monitors I had from my PC. I heard it was simple to connect using the adapter that comes with the computer. Well, everything fit great, but when I boot up my computer I get nothing. My monitor tells me it can't read the signal for the computer. Well I tried 3 VGA monitor I had and NOTHING! At one point I did get a picture, with an unreadable red tint to it. Why can't my g4 read these VGA monitors????

Steve

Try resetting the PRAM. After you hear the Mac chime hold down the following keys:

Apple, Option, P, R

Wait for it to chime 2 more times and then release those buttons and then see if you can see a picture. The previous owner may of jacked the screen resolution up too high for your displays. Also can you check with another computer (Mac or PC) to see if those displays actually work. You may also have a bad adapter. If you have an Apple Retail Store near by then take the adapter there and have them test it out for you. I'm sure they'll do it for free.

 

[Steve713]

Strange, especially if you checked the old VGA monitors refresh rate and resolution to as set the video card up to drive the monitor using something that would work.

What exactly do you mean? I can't even see anything to change any setting! I could bring the monitors back to my PC and change setting there on the PC. Will that help.. will they save in the monitor?

Please Help!

 

[blue&whiteman]

could be a bad video card. just a thought...

 

[Steve713]

Try resetting the PRAM. After you hear the Mac chime hold down the following keys:

Apple, Option, P, R

Wait for it to chime 2 more times and then release those buttons and then see if you can see a picture. The previous owner may of jacked the screen resolution up too high for your displays. Also can you check with another computer (Mac or PC) to see if those displays actually work. You may also have a bad adapter. If you have an Apple Retail Store near by then take the adapter there and have them test it out for you. I'm sure they'll do it for free.

No luck! Any other ideas?

 

[Steve713]

could be a bad video card. just a thought...

Nope worked fine 2 days ago with an apple display!

Am I missing something?

 

[blue&whiteman]

vga is vga. macs have used the same display connector as pc for 5 or 6 years now. I'm stumped.

 

[Sun Baked]

you'll probably need to use the monitor that has the bad red tint -- then go to the control panels/system preferences and change the monitors/display settings to something that the monitor will read.

How do you know what the monitor will read -- use the monitor's manual or download one.

Some people will set the video card to an extremely high refresh rate (aka the stuff that says 640x480 @ 60-120Hz) -- or use a resolution that some monitors may not support.

Best guess would be the card is set to a normal resolution, but really high refresh rate. And the monitors are refusing to sync with the computer.

---

Hopefully you're pluging it directly into the VGA port on the computer if it has one, if you're using one of the old beige days VGA-to-Mac VGA display convertor/adapter it'll switch the signal to sync-on-green (which is used for the old beige days Mac VGA displays).

Of course that's just as bad as using a MacVGA-to-VGA adapter.

 

[mklos]

Nope worked fine 2 days ago with an apple display!

Am I missing something?

can you test it with the display again just to see if it is infact the graphics card?

If not then like I said before it could be a bad DVI to VGA adapter.

If you look on eBay you can do a search for a 17" Flat CRT Apple Studio Display. These a very nice displays and are selling for around $200, sometimes less. They also use the ADC connector. Just an option...

 

[blue&whiteman]

I think sun baked may be onto something there. makes sense.

 

[Steve713]

I think sun baked may be onto something there. makes sense.

Thanks guys I grateful for the help.

Right now I can't get any of the monitors to show up. I've reseted several times hold down the P R opiton apple keys and still nothing.

Here are the specs of the monitor I just bought today. Should this monitor be working?

Specifications
Size: 17 inches
Screen Size: Flat 16" viewable
Dot Pitch: 0.25mm
Resolution: 1280 x 1024 @ 60 Hz
Features: Non-glare, Plug & Play, Energy Star compliant
Dimensions: 16.5"w x 16"h x 17.25"d
Weight: 39 lbs.
Tech. Specs.: 30~70 KHz (horizontal)
50~160 Hz (vertical)
AC 110~240V 60/50 Hz

I know, I know its an emachine, but it should work right?

Can I reset to 800x600 during boot up?

 

[Sun Baked]

I think the video cards default to 640x480 @ 60Hz when you reset the PRAM, so the monitor should show something until the OS loads the OS video card settings.

If you have a ADC and a VGA port -- no other adapter is needed since all non-beige Mac should use standard PC VGA.

If you have the MacVGA adapter from your old Mac monitor, you don't need it. (this is all I can think of when you say the old Mac monitor worked, but not the PC monitors).

Unless it was an ADC monitor on the other port that was working -- since a bad video out port is always possible.

 

[javabear90]

this happened to me on a pc. It was a dead cable. One of the pins was broken. The problem might be a cable or an adapter of somesort. Check out those and try different ones if you can. Hope this is a help!