Takeshi7 wrote:I just want to give an update on this. My friend helped me delid the CPU with his hot air workstation. Once it was delidded we added a bit more solder and used a soldering iron to make sure the solder was nicely spread on both the CPU dies and the IHS. ( the IHS was harder because it has much more thermal mass) Then we relidded it and I put it in my PC. It now runs much cooler, Even under full load it is cooler than its old idle temp. Old idle temp was around 60C, load would go above 90C, After delidding/fixing solder, the new temp under load is 48ish (idle in the low 30s now). I will update this comment with a link to the Youtube video once I have it.
tl;dr: Yes the solder under the IHS can go bad, and it is possible to fix by delidding.
Never before has such an obsolete CPU owed so much to so few.
Glad it worked!