Is it true that you need to use a bigger PSU in AGP/GE G4s when using an ATI 9800?

Is it true that you need to use a Power Supply with more Watts in an AGP or GigabitEthernet PowerMac G4 when using an ATI 9800?

Sawtooth, possibly, yes (qualified).

Gigabit Ethernet, no (qualified).

(or only, when using a CPU Upgrade at the same time?)

This is one of those qualifications.

If you have a Sawtooth with a 7447 processor, a 9800 Pro and one hard drive, no PCI cards other than a USB 2.0, then the Sawtooth PSU will likely be fine as is.

Just don't run it too hard in a too hot of an environment. I had one that was fine until August, then heat and PSU weakness combined to create issues.

Even in a cool room, if you add another hard drive, another PCI card or two and try to burn some DVDs or play an extended Doom 3 session, heat will begin to cause the Sawtooth PSU to get flaky.

This is when a bigger PSU is desired. The OEM PSU does not do well with load when hot.

I went through it all and wrote it up here:

http://www.jcsenterprises.com/Japamacs_Page/The_Sawtooth.html

The Gigabit Ethernet PSU will handle a processor upgrade, a 9800 Pro, a PCI card (or 2) and two drives much better than the Sawtooth.

My formerly DP 450 GE turned DP 1.6 GHz with 9800 Pro and two drives was always stable with the OEM PSU, regardless.

I heard the ATI Radeon 9800 needs about 300W max., so one should have a 430W supply to be sure. Is that right?

No. A 300 W PSU is recommended in the system that the 9800 Pro will be installed in.

A standard clocked Pro needs about 35 W. An OC'd Pro needs up to 55 W. Add a bit more for requisite cooling mods; HEAT becomes the issue, fast.

If one is going to the trouble to adapt and install a new PSU, I think a little more is better than just enough.

There isn't much sense in putting in a PSU that is going to be running near peak all the time.

I wouldn't mess with less than 350. The 550 that I chose was more about features and price than the 550W rating.

Nothing around 400W appealed to me or was affordable at the time.

Definitely look at the quality of the PSU/power output, as well as the rail structure.

Zalman made a passive heatsink for the 9800. A massive aluminium sandwich which often still needed a fan.

Nothing beats an Arctic Cooling Silencer, but those are very rare.

The Zalman VF700 ** and VF900 ** are excellent coolers but don't vent out of the case like the Silencer.

There's one for $15 shipped here.

http://www.ebay.com/itm/ARCTIC-COOLING-ATI-SILENCER-1-Rev-2-/111016261063?pt=US_ Video_Card_GPU_Cooling&hash=item19d915b5c7

Wow, great find Dave! 🙂

I have three....... will have to list them one of these days.