Hello! Today I come with another strange question. I've been looking into iMac G4's for several months now, but I've always been bothered by the LCD display. It was the newest flat screen technology at the time, but it's colors seem bland now in comparison to an OLED. I was wondering if it is at all possible to replace the LCD screen with an OLED for better colors. It's not a *need* but it would be wonderful if possible. Thank you in advance.
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Can the iMac G4 screen be changed?
- Thread starter SaturnOfThePast
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The short answer is that it is not going to be easy, though most things are possible with enough time and soldering.
I am pretty sure that there aren’t any drop-in OLED replacement panels. The iMac G4 panels are CCFL-backlit and have the inverter in the screen enclosure. The panels are interfaced via TMDS (like DVI/HDMI) rather than LVDS or (what an OLED panel almost certainly uses) eDP.
The venerable DremelJunkie guides (http://www.dremeljunkie.com/2011/08/guide-step-by-step-17-imac-g4-tmds-to.html?m=1) approach this problem from the other side, adapting the iMac’s original display to work with a DVI connector so it can be run from a normal computer.
Another instance of prior work in this area is this case modder who built an entirely new display frame for his iMac and put a modern Intel motherboard in.
SinoNeptune’s iMac G4 Mod with reproduced screen and Android system
SinoNeptune’s iMac G4 Mod with reproduced screen and Android system Hello everyone, I’m an architect and MOD amateur from China. It’s really great pleasure to find this site which so many wonderful mod work of iMac G4. I study a lot here and also did one by my own. I’d like to share it with...
www.tonymacx86.com
For many laptop displays, there exist driver boards that will let you drive them via HDMI. In theory, you could connect one of these driver boards to the TMDS outputs of the iMac, although you may have to spoof the EDID to match that of the original panel.
I also could not find any OLED panels readily available on the second-hand market, which means there probably aren’t many driver boards out there yet.
Another potential challenge is that the iMacs have a 4:3 (15”) or 16:10 (17” and 20”) aspect ratio panel, and most new panels out there are 16:9, meaning that they wouldn’t fit into the original frame well. Even if there were a 16:10 panel available, odds are good that it wouldn’t mechanically mount to the same points.
So to retrofit an OLED panel, you’d need to solve the following:
- Interface the iMac TMDS to whatever protocol the OLED uses and get the iMac to recognise it
- Adapt the CCFL inverter or its control signals to run the brightness on the OLED panel
- Mechanically adapt the OLED panel to mount in the iMac display frame
All of these are certainly possible, but they represent a pretty significant reverse engineering challenge. If I haven’t scared you off and you go ahead with this, please keep us posted!
I'm still interested in doing this project, but it appears my options in screens are *extremely* low as you have said. I was wondering, would it be any different if I were to use a LED screen? I know OLED and LED are very different, but it would still be better than a nearly 20 year-old LCD. I thank you again in advance.The short answer is that it is not going to be easy, though most things are possible with enough time and soldering.
I am pretty sure that there aren’t any drop-in OLED replacement panels. The iMac G4 panels are CCFL-backlit and have the inverter in the screen enclosure. The panels are interfaced via TMDS (like DVI/HDMI) rather than LVDS or (what an OLED panel almost certainly uses) eDP.
The venerable DremelJunkie guides (http://www.dremeljunkie.com/2011/08/guide-step-by-step-17-imac-g4-tmds-to.html?m=1) approach this problem from the other side, adapting the iMac’s original display to work with a DVI connector so it can be run from a normal computer.
Another instance of prior work in this area is this case modder who built an entirely new display frame for his iMac and put a modern Intel motherboard in.
SinoNeptune’s iMac G4 Mod with reproduced screen and Android system
SinoNeptune’s iMac G4 Mod with reproduced screen and Android system Hello everyone, I’m an architect and MOD amateur from China. It’s really great pleasure to find this site which so many wonderful mod work of iMac G4. I study a lot here and also did one by my own. I’d like to share it with...
For many laptop displays, there exist driver boards that will let you drive them via HDMI. In theory, you could connect one of these driver boards to the TMDS outputs of the iMac, although you may have to spoof the EDID to match that of the original panel.
I also could not find any OLED panels readily available on the second-hand market, which means there probably aren’t many driver boards out there yet.
Another potential challenge is that the iMacs have a 4:3 (15”) or 16:10 (17” and 20”) aspect ratio panel, and most new panels out there are 16:9, meaning that they wouldn’t fit into the original frame well. Even if there were a 16:10 panel available, odds are good that it wouldn’t mechanically mount to the same points.
So to retrofit an OLED panel, you’d need to solve the following:
- Interface the iMac TMDS to whatever protocol the OLED uses and get the iMac to recognise it
- Adapt the CCFL inverter or its control signals to run the brightness on the OLED panel
- Mechanically adapt the OLED panel to mount in the iMac display frame
All of these are certainly possible, but they represent a pretty significant reverse engineering challenge. If I haven’t scared you off and you go ahead with this, please keep us posted!
In short: using any panel besides the ones in the iMac already will involve a similar amount of trickery as getting an eDP panel working, since TMDS panels are pretty old tech and anything newer will be LVDS or eDP.
If you just want an LED backlight option, there are kits that let you swap out the CCFL tubes in the existing LCD for LED strips.
355mm LED Backlight Strip Kit,Update 17" 17 inch CCFL LCD Screen to LED Monitor | eBay
LED strip size:355x4mm. 2x LED strip. If your monitor is using a inverter, then this kit replace the inveter to plug into the driver board ;. Driver board size:7x2cm. 1x Driver board. with the ON / OFF.
www.ebay.com
That has you still using the original TN panel, though. If you want an IPS panel, it’s theoretically possible to find a 17” IPS panel that accepts TMDS signalling, but I haven’t found any.
Rumor has it that the 20” G4 is IPS, but I found one 20” IPS panel as well, the LM201W01-STB1. It is CCFL-backlit, though, and is from 2007. So not too much newer.
If you did go with swapping the existing panel for a different TMDS one, you would probably need an EDID interposer like the UniMac V4, though it is targeting the LVDS panels in 2006-era Intel iMacs.
iMac Intel 17" UniMac V4 Adapter Kit
This Adapter Kit is used to replace the LCD screen in the iMac 17" Intel model. These models are notorius for developing hundreds of vertical lines...
www.ifixit.com
How to fix your iMac - Real Mac Mods
How to fix vertical lines on your iMac screen. The UniMac V4 Kit can be used to replace your LCD and the lines will be gone forever.
You could also go for a more recent LVDS or eDP panel in the same aspect ratio and try to convert the TMDS signals from the iMac to LVDS using an HDMI driver board (like I was proposing previously), though that would be more involved. The other issue is that it will be hard to find new panels in the 4:3 or 16:10 aspect ratios. This is why most iMac G4s that are modified to have new internals and a new screen wind up with a totally new monitor on the end of the arm.
Personally, the viewing angles on my 15” G4’s TN panel don’t bother me that much since it’s attached to the amazing arm which allows me to position and tilt it to point right at me...
I would probably do the LED backlight upgrade if the CCFLs went out.
This isn't particularly what you were looking for, but it is an option.
I am pretty sure iMac G5 displays are more compatible with the iMac G4s. The G5s have slightly better displays.
I have a 17" G4 and I am fine with it's display personally. But next to my 20" G5, there is definitely a visible difference.
I am pretty sure iMac G5 displays are more compatible with the iMac G4s. The G5s have slightly better displays.
I have a 17" G4 and I am fine with it's display personally. But next to my 20" G5, there is definitely a visible difference.
Update:
I took out the inverter and found that the fuse is burned. Could anyone help identify the model and suggest a replacement?
Thanks a lot!
====Below is original post====
Hi, I have an iMac G4 800 17in, the backlight is out after fan replacement. I think the inverter needs to be replaced. However, I saw a post mentioning this LED kit can be used:
The seller describe the pinout of the kit as below:
VIN : voltage
ENA: on/off
DIM: ADJ adjust brightness
GND: connecting Ground
Can anyone help to figure out how to wire it to iMac? Thanks a lot!
https://i.ebayimg.com/images/g/ovQAAOSwu4BVwXkZ/s-l1600.jpg
I took out the inverter and found that the fuse is burned. Could anyone help identify the model and suggest a replacement?
Thanks a lot!
====Below is original post====
Hi, I have an iMac G4 800 17in, the backlight is out after fan replacement. I think the inverter needs to be replaced. However, I saw a post mentioning this LED kit can be used:
355mm LED Backlight Strip Kit,Update 17" 17 inch CCFL LCD Screen to LED Monitor | eBay
LED strip size:355x4mm. 2x LED strip. If your monitor is using a inverter, then this kit replace the inveter to plug into the driver board ;. Driver board size:7x2cm. 1x Driver board. with the ON / OFF.
www.ebay.com
VIN : voltage
ENA: on/off
DIM: ADJ adjust brightness
GND: connecting Ground
Can anyone help to figure out how to wire it to iMac? Thanks a lot!
https://i.ebayimg.com/images/g/ovQAAOSwu4BVwXkZ/s-l1600.jpg
Last edited:
Hi, Needelroozer, my 17in imac g4 inverter is broken, could I replace the inverter with the LED backlight kit? Thank you!In short: using any panel besides the ones in the iMac already will involve a similar amount of trickery as getting an eDP panel working, since TMDS panels are pretty old tech and anything newer will be LVDS or eDP.
If you just want an LED backlight option, there are kits that let you swap out the CCFL tubes in the existing LCD for LED strips.
355mm LED Backlight Strip Kit,Update 17" 17 inch CCFL LCD Screen to LED Monitor | eBay
LED strip size:355x4mm. 2x LED strip. If your monitor is using a inverter, then this kit replace the inveter to plug into the driver board ;. Driver board size:7x2cm. 1x Driver board. with the ON / OFF.www.ebay.com
That has you still using the original TN panel, though. If you want an IPS panel, it’s theoretically possible to find a 17” IPS panel that accepts TMDS signalling, but I haven’t found any.
Rumor has it that the 20” G4 is IPS, but I found one 20” IPS panel as well, the LM201W01-STB1. It is CCFL-backlit, though, and is from 2007. So not too much newer.
If you did go with swapping the existing panel for a different TMDS one, you would probably need an EDID interposer like the UniMac V4, though it is targeting the LVDS panels in 2006-era Intel iMacs.
iMac Intel 17" UniMac V4 Adapter Kit
This Adapter Kit is used to replace the LCD screen in the iMac 17" Intel model. These models are notorius for developing hundreds of vertical lines...How to fix your iMac - Real Mac Mods
How to fix vertical lines on your iMac screen. The UniMac V4 Kit can be used to replace your LCD and the lines will be gone forever.realmacmods.com
You could also go for a more recent LVDS or eDP panel in the same aspect ratio and try to convert the TMDS signals from the iMac to LVDS using an HDMI driver board (like I was proposing previously), though that would be more involved. The other issue is that it will be hard to find new panels in the 4:3 or 16:10 aspect ratios. This is why most iMac G4s that are modified to have new internals and a new screen wind up with a totally new monitor on the end of the arm.
Personally, the viewing angles on my 15” G4’s TN panel don’t bother me that much since it’s attached to the amazing arm which allows me to position and tilt it to point right at me...
I would probably do the LED backlight upgrade if the CCFLs went out.
Update: I took out the inverter and found that the fuse is burned, could anyone help me identify the model and suggest a replacement? Thanks a lot!
Update:
I took out the inverter and found that the fuse is burned. Could anyone help identify the model and suggest a replacement?
Thanks a lot!
====Below is original post====
Hi, I have an iMac G4 800 17in, the backlight is out after fan replacement. I think the inverter needs to be replaced. However, I saw a post mentioning this LED kit can be used:
The seller describe the pinout of the kit as below:355mm LED Backlight Strip Kit,Update 17" 17 inch CCFL LCD Screen to LED Monitor | eBay
LED strip size:355x4mm. 2x LED strip. If your monitor is using a inverter, then this kit replace the inveter to plug into the driver board ;. Driver board size:7x2cm. 1x Driver board. with the ON / OFF.www.ebay.com
VIN : voltage
ENA: on/off
DIM: ADJ adjust brightness
GND: connecting Ground
Can anyone help to figure out how to wire it to iMac? Thanks a lot!
https://i.ebayimg.com/images/g/ovQAAOSwu4BVwXkZ/s-l1600.jpg
Dremeljunkie’s site has a pinout for the 17” inverter, though he does it by wire color rather than pin position. Probably you can match up the colors from the wiring harness, though:
Blue - 12V - VIN
Red - ON/OFF - ENA
Green - Sleep/Wake - ENA via series 1kOhm
White/Orange - Dimming - DIM
Black - Ground - GND
GUIDE: Step by Step 17" iMac G4 TMDS to DVI Conversion - 800mhz and 1/1.25 Ghz Necks Completed
Mac Mini identifying monitor as "iMac" This is a step-by-step detailing the process of converting a 17" iMac G4 to a useable LCD with ...
If this is similar to the LED boards people use in the iBook G3, you may need to rework the driver board so that the dimming function isn’t inverted.
Blueberry iBook G3 Clamshell LCD Backlight replacement
It can be… up and to the moment when you need to remove the OEM inverter board (anchored to the back of the display assembly, behind the LCD) and put in the LED board. Also, if you’re using a generic LED-conversion kit, you should know that brightness control will be inverted and you won’t be...
forums.macrumors.com
Upgrading iBook Clamshell Display?
Hello! I finally have time to get back to my Macs after my surgery, and I noticed that my clamshell's display panel is problematically dim even at full brightness. Can the panel be swapped out, and if so what's the best replacement option?
68kmla.org
For your inverter fuse, I would measure its length to verify its package size, but it looks like a 1206 2A fuse, and any replacement in that package and rating will probably be just fine.
Here’s a thread where somebody had a very similar inverter fuse blow:
Need help finding replacement SMD fuse - Page 1
Need help finding replacement SMD fuse - Page 1
www.eevblog.com
Thanks so much to ptfuzi and Needleroozer!Dremeljunkie’s site has a pinout for the 17” inverter, though he does it by wire color rather than pin position. Probably you can match up the colors from the wiring harness, though:
Blue - 12V - VIN
Red - ON/OFF - ENA
Green - Sleep/Wake - ENA via series 1kOhm
White/Orange - Dimming - DIM
Black - Ground - GND
GUIDE: Step by Step 17" iMac G4 TMDS to DVI Conversion - 800mhz and 1/1.25 Ghz Necks Completed
Mac Mini identifying monitor as "iMac" This is a step-by-step detailing the process of converting a 17" iMac G4 to a useable LCD with ...www.dremeljunkie.com
If this is similar to the LED boards people use in the iBook G3, you may need to rework the driver board so that the dimming function isn’t inverted.
Blueberry iBook G3 Clamshell LCD Backlight replacement
It can be… up and to the moment when you need to remove the OEM inverter board (anchored to the back of the display assembly, behind the LCD) and put in the LED board. Also, if you’re using a generic LED-conversion kit, you should know that brightness control will be inverted and you won’t be...Upgrading iBook Clamshell Display?
Hello! I finally have time to get back to my Macs after my surgery, and I noticed that my clamshell's display panel is problematically dim even at full brightness. Can the panel be swapped out, and if so what's the best replacement option?
For your inverter fuse, I would measure its length to verify its package size, but it looks like a 1206 2A fuse, and any replacement in that package and rating will probably be just fine.
Here’s a thread where somebody had a very similar inverter fuse blow:
Need help finding replacement SMD fuse - Page 1
Need help finding replacement SMD fuse - Page 1www.eevblog.com
So happy to see those wonderful mod posts! I just ordered a 1206 2A fuse from amazon. If changing the fuse does not fix the issue, I will move forward to the led backlight plan.
Fielect SMD Fuse 63V 2A SMD Fast Acting Fuse 1206 Surface Mount Chip for Com-Communications Overcurrent Protection 10Pcs
Material：Metal Max Current: 2A Max Voltage: 63V Size:3mm x 2mm x 0.5mm/0.12"x0.08"x0.02"(L*W*T) 1.These resettable fuses are used to help protect against harmful overcurrent surges and overtemperature faults. 2.The fuse can play the role of overcurrent protection,which is to ach...
www.amazon.com
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
Update:
After replacing the fuse with a 1206 fuse (63V, 2A) bought from amazon, the screen is back! Please ignore the poor soldering job.
After replacing the fuse with a 1206 fuse (63V, 2A) bought from amazon, the screen is back! Please ignore the poor soldering job.
Fielect SMD Fuse 63V 2A SMD Fast Acting Fuse 1206 Surface Mount Chip for Com-Communications Overcurrent Protection 10Pcs
Material：Metal Max Current: 2A Max Voltage: 63V Size:3mm x 2mm x 0.5mm/0.12"x0.08"x0.02"(L*W*T) 1.These resettable fuses are used to help protect against harmful overcurrent surges and overtemperature faults. 2.The fuse can play the role of overcurrent protection,which is to ach...
www.amazon.com
Update:
I took out the inverter and found that the fuse is burned. Could anyone help identify the model and suggest a replacement?
Thanks a lot!
====Below is original post====
Hi, I have an iMac G4 800 17in, the backlight is out after fan replacement. I think the inverter needs to be replaced. However, I saw a post mentioning this LED kit can be used:
The seller describe the pinout of the kit as below:355mm LED Backlight Strip Kit,Update 17" 17 inch CCFL LCD Screen to LED Monitor | eBay
LED strip size:355x4mm. 2x LED strip. If your monitor is using a inverter, then this kit replace the inveter to plug into the driver board ;. Driver board size:7x2cm. 1x Driver board. with the ON / OFF.www.ebay.com
VIN : voltage
ENA: on/off
DIM: ADJ adjust brightness
GND: connecting Ground
Can anyone help to figure out how to wire it to iMac? Thanks a lot!
https://i.ebayimg.com/images/g/ovQAAOSwu4BVwXkZ/s-l1600.jpg
As an Amazon Associate, MacRumors earns a commission from qualifying purchases made through links in this post.
I'd love to have more info on that. My G4 20" screen is dead and wondering about G5 or early C2D compatibility
The polycarbonate Intel iMacs use an LVDS rather than TMDS interface, but the G5s still have TMDS panels and are compatible.
Finding a upgrade display for iMac G4 is not trivial, considering that they (at least the 17" and 20" models) use the 16:10 display ratio.
I have done some searching trying finding a 20" display with 16:10 ratio and at least 1920x1200 in resolution, but that have so far turned out nil. (If anyone knows where to find such a thing, please share!)
If you are looking to upgrade the display of a 17" iMac G4, a possibility is to use a display from a MacBook Pro, like this guy did:
Specifically I believe these MacBook Pro models were available with a 1920x1200 (= 16:10 ratio) display (optional for some models) :
A1229, 2007-2008
A1261, 2008-2009
A1297, 2009-2012
Caveat: Depending on what you have on the inside of the G4, the magic needed to actually hook up such a display may vary. I have not done it myself (Yet. Still on the lookout for one of these MacBook at a fair price + screen intact), so I cannot give any more guidance on how to actually do it.
Last edited:
There is also the Dell XPS 17", which has a 16:10 display in FHD+, 1920 x 1200 or UHD+, 3840 x 2400 ,
but that will cost a bit... https://www.dell.com/ae/p/xps-17-9700-laptop/pd
These LCDs use an embedded DisplayPort (eDP) interface so would need an adapter to interface with the iMac. And there's no way in hell an iMac G4 is going to drive an 3840×2400 display at any comfortable refresh rate!
Dell are getting the acronyms wrong (how dare they
)1920×1200 = WUXGA
3840×2400 = WQUXGA
true thatThese LCDs use an embedded DisplayPort (eDP) interface so would need an adapter to interface with the iMac. And there's no way in hell an iMac G4 is going to drive an 3840×2400 display at any comfortable refresh rate!
Dell are getting the acronyms wrong (how dare they
1920×1200 = WUXGA
3840×2400 = WQUXGA
I realize I deviated a bit from the original question, was thinking more about my own plans of modding the G4 with an M1 or some other more modern hardware Hello everyone, i'm a reverse query.
I have a 20" G4 USB 2.0 that the motherboard does not recognize the hd/cdrom drives. I would like to use the panel and connect an old macmini i7 from 2012 or a Raspberry PI to it, is it possible?
Thank's
I have a 20" G4 USB 2.0 that the motherboard does not recognize the hd/cdrom drives. I would like to use the panel and connect an old macmini i7 from 2012 or a Raspberry PI to it, is it possible?
Thank's