First post, by Lotosdrache
@Skalabala, @Roman555, and @all those interested
Finally after more than one year, I had some time during last week to do some measurements on my Jetway 542C and Gigabyte GA-5AX in order to find the A19 address line and its connection points to L2 cache, TagRAM, and northbridge:
On the green lines I measured an electrical resistance of 0 Ohm (okay it was 0.2 Ohm 😉 )
Gigabyte GA-5AX:
Jetway 542C:
As you can see, there are some differences starting at the CPU:
- L2 cache chip on the Gigabyte is separated by an extra resistor R46 from A19 line whereas on the Jetway R304 is in front of both L2 cache and TagRAM chip
- Coming from the CPU, R59 is placed in front of TagRAM Pin 1 on the Gigabyte but R21 comes afterwards on the Jetway
- Passing TagRAM Pin 1 on GA-5AX we come to missing resistor R259. Then address line A19 divides to the 10 kOhm resistor R258 (that has no equivalent on the Jetway) and to a line leading below L2 cache chip.
On both boards, I have no idea which line ends up at northbridge Pin R1 finally.
I replaced L2 cache on the J-542C...
[to be continued in next post (5 pictures per post limit 🙄 )]