First post, by Deksor
- Rank
- l33t
Hello folks !
So some time ago this nice 486 mobo was given to me (SiS 486G 3.3/5V Ver:E) (Pictures will come soon)
Even though it had fake cache and no 3.3V VRM, I knew that at least I could add those features by myself. Adding the cache took quite some time, but it wasn't difficult in itself. Once sockets were installed and the motherboard was configured properly, it worked flawlessly.
According to this documentation http://www.elhvb.com/webhq/models/486vlb3/sis486ge.txt.html, the missing regulator is a LT1085CT (-3.3 I guess), so I bought a LT1085CT-3.3 ...
Once installed, I checked the voltages coming into the socket and on the regulator's pins. I read "3.6V"
Yeah close enough ...
Then I install a 3.3V CPU hoping for the best and !! ... nothing ...
I try another CPU and ... still nothing ...
I go back to 5V, use a i486DX2, and everything's fine. Whew, the board isn't dead at least
Now I set 3.3V back, insert a 3.3V cpu back and I check the voltage on the regulator's pins ... 1.5-1.8ish volt. Uh ?! I remove the CPU, 3.6V again.
What's going on ? did-I miss something ? Is there something wrong with my mobo ? Did I buy the wrong LT1085CT regulator ?
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