At 20:38 -0800 11/05/2002, tom wrote: >I have borked the adb/cuda chip somehow by shorting it or a connection >to it. My questions are: > >Where is the little beastie located? >How hard is it to test/repair? >How would you procure a new/used one? > >I seem to recall you mentioning in passing sometime in the distant past >about scavenging one off of another motherboard for some nefarious umax >surgery and was wondering if you could enlighten us again concerning >this little piece of silicon.
The CUDA chip is behind the PCI slots near the bottom rear corner of the board (left rear on J700). The chip is labeled 341S0788. It is a custom Apple chip, so you must scavenge one from another board, but they were used on everything. I have taken them off of the 7100 and it worked fine. Some of the older ones have a slightly different part number but they're all 28 pin SOIC package chips and seem to work the same. So you could probably find a 6100 or even maybe a Quadra board with one you could scavenge. If you're particularly worried about a perfect match up, get an old 7200 board. As to testing, that's a weak area for me. I just go by symptoms and often guess correctly. If your mouse isn't rolling, you may have lost one of the lines in the CUDA chip, but you should also check for scratched or burnt traces or resistors near the CUDA chip, given the event that caused your problem. The repair is easy or difficult depending on your soldering skills. The tough part is removing the replacement part, because you need to get all 28 pins to come loose at the same time. If you need advice on that, ask and Mad Dog or I (and probably a few others such as P. Stortz) can advise you. Are you saying that mouse rolling works under Linux? If so, that sounds more like you've got a corrupt System component or something in your Mac OS install. If it works under one OS and not another, it's pretty unlikely that hte underlying cause is a hardware problem. Jeff Walther -- SuperMacs is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | Service & Replacement Parts [EMAIL PROTECTED] | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> SuperMacs list info: <http://lowendmac.com/supermacs/list.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:supermacs@;mail.maclaunch.com> To unsubscribe, email: <mailto:supermacs-off@;mail.maclaunch.com> For digest mode, email: <mailto:supermacs-digest@;mail.maclaunch.com> Subscription questions: <mailto:listmom@;lemlists.com> Archive: <http://www.mail-archive.com/supermacs%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
