[Coco] Ebay IC's quality

[iggybeans at comcast.net]

From: iggybeans at comcast.net 
To: coco at maltedmedia.com 
Sent: Wednesday, February 12, 2014 12:54:51 PM 
Subject: Re: [Coco] Ebay IC's quality 


On 2/12/2014 6:02 AM, Luis Antoniosi (CoCoDemus) wrote: 
> Hi people, 
> 
> It's not the first time I had problems with scrap IC's sold on ebay. 
> 
> My first problem appeared with commodore 64 SID chips. A lot of 10 
> chips only 5 weren't completely dead and among those 5 none of them 
> were perfect. Some had one blown channel or bad filters. 
> 
> Yeterday debugging my new wordpak2+ card I found a short circuit on 
> dram lines: RAS and AD7. I tested all connections, removed 9958, 
> removed all DRAMs and I found a bad 4464 DRAM with short circuit. Then 
> I replaced it for another dram from same lot (bought on ebay) and 
> bang: other 2 pins were shorted too. 
> 
> Then talking to Daniel I found that the VDPs I just bought are not in 
> fact V9958s but a V9938s. There weren't V9958 in 1984. These chip were 
> rebranded: 
> 
> http://www.ebay.com/itm/261031498657?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 
> 
> Ebay is a scrap and fake IC's paradise. Take care when buying cheap IC's 
> 

That is odd as the two have significant differences that limit their utility in replacing each other. 
I have four V9958 chips purchased on eBay that are all functional .