Gaming Downgrade Dashboard firmware/kernal for jtag?

[unpaidassassin]

Going back to university in a month or so. My roomates and mine 360 got the e74 red ring. We already went a head and bought a new 360 and one of my roomates is bringing a PS3. Since I'm the most "tech-savy" of the group I'm the one asked to try to fix our old one.

According to the back of the 360, it was manufactured last year in April. I was able to towel trick/overheat fan it to get it to bypass e74 so I could check the dashboard. It has dashboard kernal 2.0.9199.0 which unfortunately cannot be jtagged.

I would like to know if there is a way to downgrade the dashboard so the 360 can be jtagged. I will also attempt to fix the e74 but I don't really like messing with hardware since I prefer software side. If I can't fix the e74, I'll just try to sell it on craiglist or something.

thanks

 

[DarkCamui]

You can't. It's not the dashboard that's stopping you from doing the jtag but the upgraded bootloader that came with 85xx firmware for the Xbox 360 and it's not possible to go back due to the e-fuse R6T3 so you have to check eBay for a jtagable console.

 

[Mantis41]

Past a certain dash revision the e fuses are blown on the CPU. This stops you obtaining the CPU keys, so no JTAG.

 

[unpaidassassin]

okay thanks for input.

another question. one of my roomates has a 360 with a manufacture date from 2006 (surprise it still work) but has same dashboard kernel as the e74 one. we checked it even without any hard drive on and also a blank hard drive too. was it because this was also used and may have been refurb by microsoft?