I've finally joined the club
6100/66 DOS Compatible just like when I was a kid...the nostalgia is hitting me pretty hard at the moment
I do want to try to improve the airflow on the left half of the system where both CPUs are currently having a heat orgy. I did put a 40mm fan inside the PowerPC processor's heatsink that kept it cool to the touch...until I installed the DOS card. Now that whole half of the chassis is roasty-toasty. There are ventilation slots cut into the bottom of the case under where the HD used to be. I wonder if I could slide a low-profile exhaust fan under there since heat doesn't tend to go downwards by itself. I'm sure those vents are intended as inlet, but the PSU fan doesn't create enough pressure to pull any meaningful amount of air through there IMO. Or maybe using that fan to pull air into the case would work better...not sure if it would overwhelm the exhaust capabilities of the PSU fan though...
I'm not too worried about that since I'm no longer powering a hard drive. I checked the voltages under the current load with the PC running and they're all still at spec. Another low amperage 12v fan shouldn't be a problem.The thing is, the load on the PSU you may want to consider
No top vents. There are bottom vents under the plastic under the BlueSCSI in my picture (where the HD used to be), and then bottom vents under the PSU that the PSU fan exhausts out of. Then there are a few open "seams" in places where negative pressure could pull air in too (mostly at the rear card slot opening). But ya, it's a terrible case for airflow and the two processors are literally directly on top of each other with maybe an 1/8" between the heatsinks. So *maybe* a slim fan could go over the intake vents that are under the HD bay and flow some cooler air towards the CPU sandwich...Hey @KennyPowers, I looked at the PPC 6100 case and realized maybe only top vents in the back. Is that right? No other ventilation?
No top vents. There are bottom vents under the plastic under the BlueSCSI in my picture (where the HD used to be), and then bottom vents under the PSU that the PSU fan exhausts out of. Then there are a few open "seams" in places where negative pressure could pull air in too (mostly at the rear card slot opening). But ya, it's a terrible case for airflow and the two processors are literally directly on top of each other with maybe an 1/8" between the heatsinks.
So *maybe* a slim fan could go over the intake vents that are under the HD bay and flow some cooler air towards the CPU sandwich...
The only way to get more space between the heatsinks would be to put a different style heatsink on the 601 because it is the taller of the two...the 486 heatsink is already pretty thin as you can see in early pictures in this thread. Mounting a different heatsink would be tricky though, and the 601 is too fragile for me to be comfortable experimenting with like that. Right now I have a little 40mm fan set inside the 601 heatsink blowing down (it's flush with the top of the heatsink and sits in the center "cavity" with space under it). That was keeping the 601 cool to the touch until the 486 was installed. With the DOS card in there, the entire metal back of the card gets hot to the touch eventually, even with the lid off (I wonder if the metal lining of the lid would act like a big heatsink for the card...lol).Oh boy...
The only way to get more space between the heatsinks would be to put a different style heatsink on the 601 because it is the taller of the two...the 486 heatsink is already pretty thin as you can see in early pictures in this thread. Mounting a different heatsink would be tricky though, and the 601 is too fragile for me to be comfortable experimenting with like that.
I wonder if the metal lining of the lid would act like a big heatsink for the card.
I saw someone over on 68kmla use a blower style fan like that over the intake vents to direct fresh air towards the CPUs...wonder if that would make a noticeable difference. Smaller fan will be louder though, and any air pulled in from that spot by a traditional fan would have nowhere to go but towards the CPUs anyways...
Do you know where on 68kmla? Link?
Maybe one that doesn't draw almost 5.5W and spin at 6000RPM and sound like a jet engine thoughDual inlet centrifugal blowers could be perfect for this application:
Maybe one that doesn't draw almost 5.5W and spin at 6000RPM and sound like a jet engine though
Ya, I suppose I could try running it off the 5V line and see if it's effective...should be about 1W that way if my math is right. Startup voltage is 7V though. I'll figure something out...I'm sure it won't at 5 or 7 volts.