Seasonic PRIME Ultra 850 Titanium Power Supply

PRODUCT: PRIME Ultra 850 Titanium
PROD LINK: PRIME Ultra Titanium Product Page
PRICE: $190.54 @ NewEgg
Price is at the time of testing!

PRIME Ultra 850 Titanium – Overshoot Transient Tests
VSB On VSB to Full, 12V Off to Full, 12V

This set of tests looks to be a continued source of struggle for this platform, doesn’t it? I can forgive the little squiggle the standby rail has going on there, but once again the staggered startup on the 12V rail is neither smooth nor continuous. So, half that point will need to go again. I am very pleased to see that this unit did not immediately go into protective shutdown as some others of the PRIME design have, but because I’ve seen more than one unit do that I’m not sure that issue has been resolved.

However, I will point out once again that all PRIME units I’ve seen shut down during this test have all functioned properly when brought into a lower load first. They never fail to do full power over long periods at high temperatures as long as they are allowed to start at load levels below 100%. As this is how most units start up by nature (most rigs don’t suck more than a few watts at boot), you don’t have a thing to worry about. Crypto miners may run into that problem, but these aren’t really designed for that kind of work, to begin with. And even then, said crypto miners would need to be right at the limits of an affected unit to even get the unit’s protection to kick in.

It’s mostly a non-issue. But it’s an issue I need to score on when I see it, and I still have one PRIME Ultra Titanium left to test in the 750W.

Time for the hot box to shine. It’s a mite chilly in here, so we’ll just have to do the best we can.

PRIME Ultra 850 Titanium – Hot Load Tests
Test # +3.3V +5V +12V DC Watts/
AC Watts
Eff. P.F. Intake/
Progressive Load Tests
1 1.07A 1.07A 6.23A 86.5W/
118.6V 90.7% 0.967 25°C/
3.325V 5.04V 12.24V
2 1.5A 1.5A 13A 176.7W/
117.8V 94.3% 0.989 28°C/
3.323V 5.04V 12.24V
3 4A 4A 32A 432.6W/
117.9V 93.3% 0.991 33°C/
3.317V 5.03V 12.24V
4 6A 6A 48A 647.6W/
117.6V 92.1% 0.994 37°C/
3.314V 5.03V 12.24V
5 8A 8A 63A 852.0W/
117.6V 90.6% 0.996 40°C/
3.311V 5.02V 12.23V
Crossload Tests
CL1 12A 12A 0A 101.4W/
119.0V 87.9% 0.978 28°C/
3.311V 5.03V 12.26V
CL2 0A 0A 70A 856.7W/
116.8V 90.9% 0.996 38°C/
3.326V 5.04V 12.22V

And there you go… I couldn’t get it past forty degrees, but the unit handled it just fine. The fan came on quite a bit sooner, but still never got that loud. That said, Seasonic is not overly concerned with making things silent at the expense of proper cooling. They won’t blast the fan at you like Enhance does these days, but neither do they care too much to make their units Be Quiet.

Titanium? Of course. We’re well under the max temp spec, so there was really no chance of getting this unit in trouble there.

And because this is a Seasonic, of course, it did better with voltage regulation this time out. On the 12V that is. The 3.3V actually slipped a bit to 0.42%, the 5V is at the same 0.40%, and the 12V is now rocking 0.08%. That’s a 0.3% average, well inside what the box promised. Mythic indeed. Let’s see what the ripple looks like.

PRIME Ultra 850 Titanium – Oscilloscope
Test # +3.3V +5V +12V

12mV at worst. Looks like winning, to me. Next page!