Hello everyone I have some doubts about the authenticity of an IC chip that I own. I believe it is a relabeled part since I have two of ym2612 I was wondering how would I go about decapping one they are from the same seller and appear identical so it turns out to be real I would still have one. I do have a cnc router available if needed.
above is a picture click on it for larger.
Acid.
Powerful, nasty, corrosive, acid.
Once you have de-capped it, how are you going to determine it's real? Do you have a reference to compare it against?
Oh, and please don't use spammy popup infested imagesuck. Just attach the image to the post like any sane human.
My image is too big it won't let me and also I do have a reference right here
http://gendev.spritesmind.net/forum/viewtopic.php?p=14976
Mr_arduino:
My image is too big it won't let me and also I do have a reference right here
... so make it smaller ... ?
New Documentation: An authoritative reference on the YM2612 - Page 40 - SpritesMind.Net
Ah, that's good then. I was worried you might end up having to de-cap them both, and then you'd end up with none 
So yes, get yourself a fume cabinet, and some nitric acid, and stand well back.
Best off approaching the chemistry department of your local Uni to see if they can help you...
I wanted to provide a very clear picture and resizing it to be under 4096kb would result in loss of quality because re compressing a JPEG is a lossy process. Also I have no plans to use it once it is decaped so is there a non chemical method to do this I could cut it with my CNC router would that work I saw a picture here of a chip that appears to have been some how cut in half [CSDb] - User Forums - Buying Commodore ICs from China
I would prefer that method that way I would not have to work with dangerous chemicals and the worst part paper work 
Hmmm..
I have just had a hack around with an old dip chip. It's relatively simple to get to the core, but pretty much impossible to get the core away from the body intact. I have no idea how they did it in that picture.
I suspect the chip itself plays a big part in it. If there is a void above the silicon, then it'd come out fine. If there is no void (like there was in my chip) then I can't see how you can get it out. In that case chemistry is your friend.
Edit: its real I was just paranoid since it got hot and I check all the wires and before wiring it up I just read about fake SID chips. It turns out it had nothing to do with the chip it was the clock that was wrong. Trash this topic please.
LOL
One word: d'oh!
Ah well, we live and learn, eh?
Ordinary nitric acid isn't any use, red fuming nitric acid is required.
Absolutely... and Nitrazine as a "cooling" agent, Likely a new house and at least a small part of the neighborhood as well. --IMO-- ROFL
Doc
Docedison:
Absolutely... and Nitrazine as a "cooling" agent, Likely a new house and at least a small part of the neighborhood as well. --IMO-- ROFLDoc
Hence my comment about getting the local Uni to help out - not because they know what they're doing; purely so you have someone else to blame when it all goes wrong
B B BBut they GAVE me the Stuff how'd I know it was going to do that??? Heh... Heeh Heeehhhh...
Doc
Our chemistry teacher caused an explosion at school, by putting a piece of yellow phosphorous into red fuming nitric acid. He should have used red phosphorous, which just produces clouds of nitric oxide and is perfectly safe. Lots of the kids in the two front rows of the class got splashed with the acid and had to go to the hospital next door with acid burns, and had holes burnt in their clothing. Luckily, no one got it in their eyes. The school had to pay for new clothes.
majenko:
Oh, and please don't use spammy popup infested imagesuck. Just attach the image to the post like any sane human.
The trick is to embed the image directly, rather than use the thumbnail w/ link to Imageshack.