MP 1,1-5,1 Auxiliary power inside Mac Pro 4,1

[amccallum1]

I have an old Mac Pro 4,1 workhorse. It has the ATI Radeon HD 4870 PCIe video card, which occupies the lower two of the Mac Pro's four PCI slots. It tends to overheat in the summer and fail, so I'd like to install a Fox 2 exhaust / extractor fan above it. Looks like the intake of the fan will line up nicely with the exhaust of video card. Almost as if it was designed with it in mind. Ahem.

Problem: the Radeon video card MUST be plugged into BOTH the 6-pin auxillary power sockets on the backplane / logic board of the Mac Pro; there seem only to be two. So where could i get power to run the fan?

Thanks,

 

[Macschrauber]

I would get rid of this old power hog. They take an insane amount of power just for idling.

You can replace it with an Apple HD5770 without giving up compatibility.

 

[h9826790]

If you must keep that card.

It's time to clean the heatsink and re-apply thermal paste. Just apply some compress air from the back (the exhaust side) to push the dust out. And open the card, completely remove the old paste, and apply the new one.

I also has the 4870, it isn't that easy to overheat if the cooling system is functioning.

Adding extra fans won't solve the issue if the cooling system itself is failing.

 

[amccallum1]

I would get rid of this old power hog. They take an insane amount of power just for idling.

You can replace it with an Apple HD5770 without giving up compatibility.

Thanks – appreciate the tip: slightly more expensive than the fan+ cables, but doesn't use the other two PCIe slots. Likely quieter, too. Appreciate your wisdom.

 

[amccallum1]

If you must keep that card.

It's time to clean the heatsink and re-apply thermal paste. Just apply some compress air from the back (the exhaust side) to push the dust out. And open the card, completely remove the old paste, and apply the new one.

I also has the 4870, it isn't that easy to overheat if the cooling system is functioning.

Adding extra fans won't solve the issue if the cooling system itself is failing.

Oh, now that's interesting too. It never occurred to me, that I could open up the HD 4870 and give iot a basic cleaning and service. Shame on me. and thank you! I even have some thermal paste somewhere. Tomorrow morning's fun job! I'll let you know if it makes a noticeable difference. Thanks again – very much appreciated.

 

[Macschrauber]

The HD5770 needs one aux power.

There are a lot of better and even more energy efficient cards. But most of them dont work on old OS.

I mentioned it as it is from 2010 and also has a Mini DisplayPort.

 

[mode11]

@amccallum1 what OS are you running on your Mac Pro? What do you use the video card for? As others have mentioned, you could replace it with a much newer / more efficient video card (e.g. an RX 560) for not much money.

The RX 560 is much faster than the HD 4870, and only uses a single 6-pin connector. Plus it would allow you to run OS's up to Monterey in future, should you ever want to. Though admittedly won't have boot screen support with your current OS, unless you go down the rabbit hole of OpenCore, which isn't for everyone. Boot screen support is only really needed if you Bootcamp your Mac, though, and you could keep the 4870 in a drawer for emergencies.