Today was "G5 Quad Day". I managed to acquire two additional G5 Quad CPU cards (not an easy task these days!) and used the first one to upgrade my Air Quad back to full Quad status and the second one to do the same to my LCS Quad.
Air Quad (Air Cooled Quad): Prior to today, only one CPU card was in use because the other was damaged and I had disabled it via an Open Firmware command. Today I installed one of the two "new" CPU cards into it and I am happy to report that the operation was a success. The second card even idles a degree or two cooler (38C to 39C) than the first one, which is a good result.
LCS Quad (LCS Cooled Quad): Prior to today, only one CPU card was physically installed, because the other one was quite dead and the machine would not boot with it physically present in the box. Today I installed the second of the two "new" CPU cards into it and this operation was initially a success. Like the Air Quad result, the second card even idled cooler than its running mate (36C to 39C) - a good result. Regrettably, an old bug-a-boo raised its head shortly thereafter: the cooling loop suddenly sprang a nasty leak. I noticed CPU B shooting up into the 90C area, followed by thermal shutdown. I found and repaired the leak and am letting the silicon sealant used for the repair to set overnight before firing the Quad up again. This episode simply reminds me that Air Cooling is far superior to LCS Cooling! Air coolers don't spring leaks!
So... I'll call it one and half out of two, or a 75% success rate for the day.
I am responsible for the new LCS leak of course - after discovering an air gap in the cooling loop while installing the second CPU card, I added more cooling fluid to the loop via needle insertion. I sealed the two holes (one to insert the coolant, the other to let air escape as the coolant took its place) as well as I knew how to, and then resealed them again half an hour later. Nonetheless, the new leak was at the exact spot where I added the coolant. Clearly, one has to let the silicon sealant set for more than one hour!
The loss of coolant does not appear to have been significant, so I will try it out again tomorrow after the sealant has set overnight and see if it runs. If not, I will have to tear it down again, refill, reseal and let it sit for another day. No worries either way however. This is a set back, not a fatal blow. The LCS Quad will ride again!
Air Quad (Air Cooled Quad): Prior to today, only one CPU card was in use because the other was damaged and I had disabled it via an Open Firmware command. Today I installed one of the two "new" CPU cards into it and I am happy to report that the operation was a success. The second card even idles a degree or two cooler (38C to 39C) than the first one, which is a good result.
LCS Quad (LCS Cooled Quad): Prior to today, only one CPU card was physically installed, because the other one was quite dead and the machine would not boot with it physically present in the box. Today I installed the second of the two "new" CPU cards into it and this operation was initially a success. Like the Air Quad result, the second card even idled cooler than its running mate (36C to 39C) - a good result. Regrettably, an old bug-a-boo raised its head shortly thereafter: the cooling loop suddenly sprang a nasty leak. I noticed CPU B shooting up into the 90C area, followed by thermal shutdown. I found and repaired the leak and am letting the silicon sealant used for the repair to set overnight before firing the Quad up again. This episode simply reminds me that Air Cooling is far superior to LCS Cooling! Air coolers don't spring leaks!
So... I'll call it one and half out of two, or a 75% success rate for the day.
I am responsible for the new LCS leak of course - after discovering an air gap in the cooling loop while installing the second CPU card, I added more cooling fluid to the loop via needle insertion. I sealed the two holes (one to insert the coolant, the other to let air escape as the coolant took its place) as well as I knew how to, and then resealed them again half an hour later. Nonetheless, the new leak was at the exact spot where I added the coolant. Clearly, one has to let the silicon sealant set for more than one hour!
The loss of coolant does not appear to have been significant, so I will try it out again tomorrow after the sealant has set overnight and see if it runs. If not, I will have to tear it down again, refill, reseal and let it sit for another day. No worries either way however. This is a set back, not a fatal blow. The LCS Quad will ride again!
