There is no one cause of the E74 RROD. It's been suggested that MS used a brittle type of lead free solder which breaks under extreme heat and the associated expansion/ contraction, it's also been suggested the X-Clamps can warp the motherboard under extreme heat from the metal casing not being perfectly flat. Both of those will only be an issue if there's excessive heat, which is common on the first revision console.
It's known the E74 RROD issues cost Microsoft over $1 billion in repair/ replacement bills. Any issues with solder would have been quickly fixed as it would have saved them $$$ in repair bills. As for the X-Clamps, they were still being used on the RROD free Jaspers and are still used on the Slim's. So I really doubt the X-Clamps were the cause of the issues. On a first generation console the CPU tends to run as hot or hotter than the GPU, the CPU uses the same solder/ X-Clamps yet doesn't suffer from failure.
XBOX360 consoles can be very reluctant to speed up their fans to keep the noise down, by default they run at 40%. An original XBOX360 console doesn't increase the fan speeds until the GPU reaches ~083°C, and won't shutoff from overheating until the GPU reaches 110°C or the ED-RAM reaches 117°C. It is possible even on a retail console to change these temperatures at which the console will increase the fan speeds, it's been suggested that if you keep the GPU under 60°C it should be relatively safe from E74 RROD/ GPU Failure particularly if this was done from early in the consoles lifespan.
The second revision of XBOX360 included an additional heatsink on the GPU to reduce the temperatures, however dust is still a severe problem. It's not so much the dust on fans which is an issue, dust clogs up the fins on the heatsinks which prevents them from moving air. On a 3 year old console which has seen a fair amount of use, this will be effecting the temperatures enough for it to massively increase the chance of E74 RROD.. You need to strip the console down and get the hoover out to remove the dust, compressed air wont help and if anything could make it worse.
Then there's the other big issue, the GPU's were fabbed by TMSC. TMSC were responable for Nvidia's GPU Failures, and it's believed this same issue effects the XBOX360's GPU from the same period. It's known that many GPU's on consoles which E74 RROD are done for, reballing/ reflowing/ towel trick doesn't always work. many people believe this to be the true cause of the RROD issues.
Then you have the 3rd issue, underneath the GPU heatsink is not only a GPU but also the ED-RAM both of which generate heat. It's known that in some cases there can be a slight height difference between the dies, and thanks to poor/ poorly applied thermal paste the ED-RAM runs hot. By simply replacing the thermal compound, i've had a console (3 years old) which saw a drop of 8°C on the GPU, and 21°C on the ED-RAM (fans @ 100%). I've also noticed the thermal compound they use sees a slighlt dropoff on consoles which are 3+ years old
Jaspers, The last revision of the old style console is known to be pretty much free of the E74 RROD issues.
It's known the E74 RROD issues cost Microsoft over $1 billion in repair/ replacement bills. Any issues with solder would have been quickly fixed as it would have saved them $$$ in repair bills. As for the X-Clamps, they were still being used on the RROD free Jaspers and are still used on the Slim's. So I really doubt the X-Clamps were the cause of the issues. On a first generation console the CPU tends to run as hot or hotter than the GPU, the CPU uses the same solder/ X-Clamps yet doesn't suffer from failure.
XBOX360 consoles can be very reluctant to speed up their fans to keep the noise down, by default they run at 40%. An original XBOX360 console doesn't increase the fan speeds until the GPU reaches ~083°C, and won't shutoff from overheating until the GPU reaches 110°C or the ED-RAM reaches 117°C. It is possible even on a retail console to change these temperatures at which the console will increase the fan speeds, it's been suggested that if you keep the GPU under 60°C it should be relatively safe from E74 RROD/ GPU Failure particularly if this was done from early in the consoles lifespan.
The second revision of XBOX360 included an additional heatsink on the GPU to reduce the temperatures, however dust is still a severe problem. It's not so much the dust on fans which is an issue, dust clogs up the fins on the heatsinks which prevents them from moving air. On a 3 year old console which has seen a fair amount of use, this will be effecting the temperatures enough for it to massively increase the chance of E74 RROD.. You need to strip the console down and get the hoover out to remove the dust, compressed air wont help and if anything could make it worse.
Then there's the other big issue, the GPU's were fabbed by TMSC. TMSC were responable for Nvidia's GPU Failures, and it's believed this same issue effects the XBOX360's GPU from the same period. It's known that many GPU's on consoles which E74 RROD are done for, reballing/ reflowing/ towel trick doesn't always work. many people believe this to be the true cause of the RROD issues.
Then you have the 3rd issue, underneath the GPU heatsink is not only a GPU but also the ED-RAM both of which generate heat. It's known that in some cases there can be a slight height difference between the dies, and thanks to poor/ poorly applied thermal paste the ED-RAM runs hot. By simply replacing the thermal compound, i've had a console (3 years old) which saw a drop of 8°C on the GPU, and 21°C on the ED-RAM (fans @ 100%). I've also noticed the thermal compound they use sees a slighlt dropoff on consoles which are 3+ years old
Jaspers, The last revision of the old style console is known to be pretty much free of the E74 RROD issues.
