Is this X2 4400 safe to sell?

Hi, doing a new system build here. Upgrading from a S939 4400 1mb cache to a 720 BE ph2.

I would like to ebay my old chip, however I have some questions if you think my chip is messed up and therefore garbage.

I have a jetway 939 sli mb. The motherboard is on her last days. Busted caps, leaking caps...etc I keep getting heat warnings from the mb, if I dont turn thermal throttling off, it beeps and says my cpu is way too hot and throttles back the pc. Now when I go to read the temps, say in everest or at bios on boot, it always says wacky numbers. Like when I boot it gives me temps that are not even of this world, like at boot it will say 1 degree C and 300 degrees F. Or sometimes itll reverse and say 150 C and 10 F. Those temps are obviously wrong. But also in everest on the chip it says CPU core 0 and 1 are at 30 to 32c idle and mid 40s under load.

So my question is, do you think both the chip and mobo are bad or just the mobo? The mobo is going in the garbage when my ph2 parts arrive, I just wanna know if I can sell the chip, I dont wanna rip someone off with a bad chip.

Also why is it that Ive seen these 939 4400 1mb cache chips going for 120 to 140 US on ebay?

Thanks in advance

Link to my new build just in case. http://www.tomshardware.com/forum/263073-31-build

sell it with a doa warranty

best thing is just explain the issue in the ad and either offer no warranty and as is - you get less or offer doa