68kMLA Classic Interface

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Is the northbridge chip burnt?
Posted by: Elv1s on 2023-07-17 02:26:04
IMG_9014.jpeg
I did a total flush and ”new blood mod” on the LCS unit (dual pump) and new thermal paste on the CPUs. Got the over temp light and checkstop after startup. Changed the CPUs for another set I got on hand (from older onepump delphi unit) but same result. So checked online and read it could be the northbridge chip so I took everything apart to get to the northbridge and after removing the heatsink I saw this. It does not look right but I hope someone could tell me if the northbridge can look like this or if this mean its dead!.
Posted by: Phipli on 2023-07-17 02:55:03
View attachment 59478
I did a total flush and ”new blood mod” on the LCS unit (dual pump) and new thermal paste on the CPUs. Got the over temp light and checkstop after startup. Changed the CPUs for another set I got on hand (from older onepump delphi unit) but same result. So checked online and read it could be the northbridge chip so I took everything apart to get to the northbridge and after removing the heatsink I saw this. It does not look right but I hope someone could tell me if the northbridge can look like this or if this mean its dead!.
If you mean the black 'paint', that's normal.
Posted by: Phipli on 2023-07-17 03:01:40
Here is a similar but not the same chip :

SlimSocial_1689588029635.jpg
Posted by: Elv1s on 2023-07-17 06:30:49
Ok, after a reasembled everything (put new fresh MX4 thermal paste on the northbridge) and made shure all screws and connections is thight I got this at start up! (Se picture) and ofcourse the over temp led and checkstop led.
Posted by: Phipli on 2023-07-17 06:51:55
Ok, after a reasembled everything (put new fresh MX4 thermal paste on the northbridge) and made shure all screws and connections is thight I got this at start up! (Se picture) and ofcourse the over temp led and checkstop led.
If I had to guess, I'd check for an airlock in your cooling system. It can be extremely difficult to get all the air out first try.
Posted by: Elv1s on 2023-07-17 07:07:52
Its my third try and I have maybe one visibel airbubbel after turning the LCS unit up side down and around.
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