Shponglefan wrote on 2024-05-02, 23:15:
Can also confirm that a Ti 4200 can run with a passive heatsink. I'm using a Zalman fanless cooler, which is basically two giant heatsinks connected via a heatpipe.
Also have a couple 140mm intake fans that help push air towards it for good measure.
Good that you've got some air blowing over it, the VRM cooling is probably the bigger issue now but you've got that solved. I discovered recently prodding around with the thermal cam that my FX5200's ISL6529 voltage regulator controller gets up to 80c in normal operation. Not the MOSFETs, the controller itself was finger burning hot and that seems like it might actually be normal? I swapped out the chip which made no difference and the ISL6529 moved to a package with a thermal ground pad on the bottom for thermal reasons.
Seems to just be a facet of older voltage regulator controllers but I did temporarily remove my voltmod to make sure I hadn't messed up
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The last few days I've been stressed out / sad because my 'expendable' Aopen AX6BC motherboard became expended. In hindsight it was a comedy of errors, I saw Necroware / scorp's video on modding early S370 boards for coppermine ability and thought I'd try the same mod (relocating the RST pin) on a celeron slotket with this board. Then there were no POST codes and I thought I had damaged the chipset.
So I swapped to another W29C020 EEPROM fresh from ebay since that's the last thing I damaged and that continued the problem. I got the 2nd board out of storage and testing that - it won't come out of reset! Oh no! Both boards are dead by my hand????
Then I put the 2nd board's EEPROM in backwards and it melted the award holographic sticker ergh. Gotta work on how to determine pin1 position when refitting chips.
Now, I like the AX6BC because it's a pretty run of the mill coppermine capable 440bx board but nothing special, however... two of them, dead? Well, they came from a scrap lot and they have a history so nothing's that simple.
BTW I probably have somewhere in the region of maybe 10 or a little more slot1 boards but this is the only one where I have a pair of them and they're both capable of doing everything I want i.e. have AGP, ISA, coppermine support, so they've become important now. Oh and they stopped being cheap and plentiful a few years back.
On the 1st board I eventually decided to clean the socket with some card sprayed with IPA and swap back to the most recently working BIOS chip, and it worked again??? slot connectors are finnicky it looks like. The new EEPROMs which are chinese remarked type chips turn out not to work with this board which means these ebay special Winbond W29C020 chips fail at the very job they were intended for. Hope they work on something else.
Seems like the slotket dirtied the slot1 contacts to stop it working, then I swapped out the EEPROM for a bad one which stopped the board working with anything else.
This was all worked out pretty quickly as soon as I pulled out the oscilloscope, I knew the processor VCC was good but the scope let me see that clocks were all working fine and the computer was trying and failing to read data from the BIOS chip. Somehow I always feel that whenever I pull out the oscilloscope, I quickly reach an unsatisfying but meaningful conclusion / understanding of what's going wrong.
The 2nd board which was stuck in reset, well when I got it, Q7 had gone pop and I don't know whether I ever tested it. I took the neighbouring Q5 transistor off since they're marked the same and tested it as an NPN.
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The same Q7 transistor gets pretty hot on the working board so idk if it's poor design or should be a PNP or what, but it'll get a heatsink. My understanding so far is that this circuit controls the ATX power on / power off maybe? The 2nd board could not be powered off after powering on via ATX power button.
Where I'd soldered the working Q5 transistor back in maybe I didn't do a good job? Reflowing the solder with fresh flux and suddenly the board is no longer stuck in reset and can POST with its original BIOS chip, so I'm back to two working AX6BC boards, hooray!!
Doing IRL stuff in the interim sure did replenish my energy for working on these though. Super glad they're both working again and I don't have to use one my fancy boards like my recently acquired Abit BH6 for general testing. In the end the faults were just 1. dirty slot1 contacts, 2. a bad chinese remarked EEPROM chip and 3. a soldering error on a transistor