Flemming
New member
So, here is some observation from me. This is solely for the sake of interest on my part... Everybody, please do not freak out 
The two MOS6581R4 i bought does not have any 'dimples' (ejector pin markings) on the top side they are practically flat/smooth (besides the notch which indicates chip orientation). This usually indicates that the chips have been sanded down and remarked. I thought i'd do some measuring on the height of the chips:
- MOS8580R5 (with dimples): 3,81mm
- MOS6581R4 (no dimples): 3,78mm
Of all the SID chips i have (i do have a few) these two 6581R4 are the only ones with no dimples, and they are slimmer than my other SIDs
Another strong indicator is their datecode: '3686', which they both have. Having several chips with similar datecode is usually very lucky. But then a friend linked me to this site ( http://kevtris.org/Projects/sid/remarked_sids.html ). The guy who owns that site obviously bought a handfull of 6581R4 with exactly the same datecode as mine - and he easily identifies them as being remarked.
Just to clarify: I am not making any accusations! No refunds, returns or anything like that! I am merely investigating and asking questions out of interest. That being said, if the chips are remarked, they should be sold as such, and it should be reflected in the price, so a partial refund might be in order.
I would like to hear from other buyers of the 6581R4 type:
- Is your datecode identical to mine (MOS6581R4 3686)?
- Does the thickness/height of the chip match the height of your other SIDs?
- Dimples or no dimples?
Here is a photo of the two 6581R4 (no dimples) along with the 8580R5 (yes dimples)

And here is a photo from Stone Oakvalley's site, where the dimples are very obvious and the printing is different from the ones above

The two MOS6581R4 i bought does not have any 'dimples' (ejector pin markings) on the top side they are practically flat/smooth (besides the notch which indicates chip orientation). This usually indicates that the chips have been sanded down and remarked. I thought i'd do some measuring on the height of the chips:
- MOS8580R5 (with dimples): 3,81mm
- MOS6581R4 (no dimples): 3,78mm
Of all the SID chips i have (i do have a few) these two 6581R4 are the only ones with no dimples, and they are slimmer than my other SIDs
Another strong indicator is their datecode: '3686', which they both have. Having several chips with similar datecode is usually very lucky. But then a friend linked me to this site ( http://kevtris.org/Projects/sid/remarked_sids.html ). The guy who owns that site obviously bought a handfull of 6581R4 with exactly the same datecode as mine - and he easily identifies them as being remarked.
Just to clarify: I am not making any accusations! No refunds, returns or anything like that! I am merely investigating and asking questions out of interest. That being said, if the chips are remarked, they should be sold as such, and it should be reflected in the price, so a partial refund might be in order.
I would like to hear from other buyers of the 6581R4 type:
- Is your datecode identical to mine (MOS6581R4 3686)?
- Does the thickness/height of the chip match the height of your other SIDs?
- Dimples or no dimples?
Here is a photo of the two 6581R4 (no dimples) along with the 8580R5 (yes dimples)

And here is a photo from Stone Oakvalley's site, where the dimples are very obvious and the printing is different from the ones above

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