an7 failing to post after long vacation

ive been out of the country for 5 months. upon returning i suddenly
have windows registry corruption and have gained, when trying to fix
that, a computer that wont post.

i was getting post-code 4E [1] for a while. i fiddled with the CPUs
heatsink as i was going to try either a different cpu or rather to
just reseat the cpu, but i failed to get it off like usual, and ended
up just trying to post again and it worked. i was freezing in the
recovery console, and it still wouldnt post every time, only about 1
in 3. i attempted again to get the heatsink off, failed again, booted
again and now im posting and i even made it through the recovery
console. just about to try starting up windows finally and suddenly im
getting post-code 26 [2]... not even getting as far as before. is this
a power supply/motherboard/CPU problem? anyone have any hints for
getting the damn heatsink off??? i press the screwdriver into the slot
and push forward or back or any which way and the thing wont budge; i
feel like if i push any harder i will break something.

system config if it really matters:
athlon xp3000+
abit AN7
nothing else really matters i dont think. this thing has been stable
as a rock for years (well, upgraded CPU and mobo in april but all
other compononets havent changed. those worked through june).

-andy

[1] 4E: 1. Program MTRR of M1 CPU
2. Initalize L2 cache for p6 class cpu & program cpu with proper
cachable range
3. initialize is the APIC for p6 class cpu
4. on mp platform (not the case), adjust the cacheable range to
smaller one in case the cacheable ranges between each cpu are not
identical

[2] 26: 1. if early_init_onboard_generator is not defined onboard
clock generator initilaization. diable respective clock resrouce to
empty pci and dimm slots
2. init onboard PWM
3. init onboard H/W monitor devices