No Video Output

[ChewbaccaSaurus]

    Hey, everyone, I was hoping some of you might have an idea of what might be wrong. I'll start off with it's a tsoped xbox running unleash X and has been running strong for the past year or so since I did that mod. Recently I took it out and decided I wanted to play it again and it booted up just fine did it's normal stuff the dashboard loaded and then after playing one game went to a black screen. Since then the system will not output a signal at all. No error lights are displayed on the front of the console and I've tried booting with and without a disc. The hard drive sounds like it spins up and tries to access just fine. So I'm not quite sure what could have gone wrong for it to not output a video signal? Any help or ideas would be greatly appreciated. 

[Magicaldave]

Hmm. No video with no apparent diagnostics. 

Few things could be going on. I have a 1.6 with a failing video port; sometimes it seems to boot perfectly and others I have to wiggle the AV cable around a bit to get anything out of it. Try that and see if it reboots, whether or not you get video. It may be necessary to reflow or replace the video port, or just be really fiddly with it to make it work  

Of course as always try another cable and tv. It happens!

To this end, what kind of cable are you using? Composite, component, hdmi, vga?

less likely based on what you’be described but the last thing I would think of is a bad/failed BIOS. do you know what revision your motherboard is? On a 1.0 or 1.1 it’s Exceedingly easy to test this out, but otherwise you’d need a modchip to rule out a bad bios. 

[ChewbaccaSaurus]

2 minutes ago, Magicaldave said:

Hmm. No video with no apparent diagnostics. 

Few things could be going on. I have a 1.6 with a failing video port; sometimes it seems to boot perfectly and others I have to wiggle the AV cable around a bit to get anything out of it. Try that and see if it reboots, whether or not you get video. It may be necessary to reflow or replace the video port, or just be really fiddly with it to make it work  

Of course as always try another cable and tv. It happens!

To this end, what kind of cable are you using? Composite, component, hdmi, vga?

less likely based on what you’be described but the last thing I would think of is a bad/failed BIOS. do you know what revision your motherboard is? On a 1.0 or 1.1 it’s Exceedingly easy to test this out, but otherwise you’d need a modchip to rule out a bad bios. 

I'm using a pound HDMI cable for the system. I'll definitely give the original AV cables a shot and a different TV. I don't quite remember the revision of the board I know it didn't have the gpu fan and it was built in 2002. It's been a while since I've had it open so I apologize not knowing the revision. 

[Magicaldave]

Nah man you good. If 2002 + no GPU fan it’s likely a 1.1. Gotta ask to find out  

If it works with another TV or original cable, I can’t offer much besides maybe your cable has failed somehow. I would guess this is NOT the case however, as unless you’ve installed IND-BIOS and disabled the AV check it will clearly flash orange/green on startup to indicate no A/V. 

Bad bios will however not do this. Since you likely have a 1.1, crack ‘Er open if my above solutions fail and check just above the GPU heatsink (on the left of the front of the console faces you) and look for a chip with a lot of pins. If it says conexant, go down and to the left and look for the LPC port. It’s basically just 16 big holes in the mid-left portion of the board. The nearest IC to this is the console’s TSOP chip. What is it? Post everything it says on the chip. 

Depending on its model, you can do some very, very, very minor soldering to boot from another copy of the BIOS stored on the console. Here is a link from this site which shows how to split your TSOP. You may be in luck and successfully boot from another bank. Try all three. 

Don’t bother with the 3.3V lines, just bridge A18 to ground, then A19, then both. Test after each attempt