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X51 PSU arrived

Yeah, I've seen a couple of those builds with the gpu upgrade and atx psu... couldn't see if the external psu was providing just pcie 12v or atx12v as well.
 
Newest update: looks like the MOSFETs are rated for a normal operating V(in) of 4.5-25VDC... hope this thing doesn't blow up! :eek:


[edit]

Working so far!
 
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Testing is going well:

20131014_170155_zpsf5181391.jpg
 
So the way the power gets regulated properly from the PSU to the CPU happens in a couple stages:
- The MOSFETs (1 per phase) step down the DC current from the PSU from whatever the input is (usually 12VDC) down to 5VDC
- The VRM module steps that 5VDC down to whatever is directed by the CPU (based upon throttling, load, etc)

In the case of the ASRock Z77E-ITX, the MOSFETs (ON Semiconductor NCP5369 chips) have a Voltage(in) acceptable range that extends up to 25VDC for normal usage and 30VDC for peaks/surges.

So... I just plugged it right up. As an additional safety measure, I added copper heatsinks to the power regulation circuitry on the power board and upgraded the fan; temps are nice and low.

Current issue is booting with the GTX670-4GB installed, so I'm working that out; there should be plenty of power as the system only pulled ~285W from the wall with the ST45SF-G.
 
Machupo said:
So the way the power gets regulated properly from the PSU to the CPU happens in a couple stages:
- The MOSFETs (1 per phase) step down the DC current from the PSU from whatever the input is (usually 12VDC) down to 5VDC
- The VRM module steps that 5VDC down to whatever is directed by the CPU (based upon throttling, load, etc)

In the case of the ASRock Z77E-ITX, the MOSFETs (ON Semiconductor NCP5369 chips) have a Voltage(in) acceptable range that extends up to 25VDC for normal usage and 30VDC for peaks/surges.

So... I just plugged it right up. As an additional safety measure, I added copper heatsinks to the power regulation circuitry on the power board and upgraded the fan; temps are nice and low.

Current issue is booting with the GTX670-4GB installed, so I'm working that out; there should be plenty of power as the system only pulled ~285W from the wall with the ST45SF-G.
Click to expand...

So most likely Dell didn't do anything to their motherboard. Seems to match up with what I've found of a handful of people using that PSU. Interested to see how it turns out, good luck.
 
Still trying to work out why it won't boot with the 670 (ostensibly it's not power, b/c there are numerous people -- on the internet -- running a 670 FTW in their x51 systems). Tried it with a T-series processor swapped in, no dice. Next test is a 650 on the pcie... should be less amperage. I also may have a "bad" power board.

Lots of stuff to try.
 
650 is a no boot... hrmm, so either I've got some bad wires, a short to ground or my power board is crap; either way, whenever I plug something into the pcie-12v port (voltages are rock solid via multimeter) I get a very brief blip from the fans and then it all shuts down.

[edit]I hope I'm not seeing things, but from images.google.com it appears that the 12v wires and ground wires switch places on the connector. ground is supposed to be near the clip, but on the power board, the blue (live) wires appear to be next to the clip... wtf?! I guess reversed phase would account for the shutdowns[/edit]
 
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what are you gonna do? repin your connector on your mobo power cable?

also, hey machupo. :) didnt see this thread until just now. do you have a log up for newtronium yet or is this it so far? (see what i did there, NEWtronium? :p;))
 
lol, it just rolls off the tongue, eh? -- yep, repinned the pcie power cable (that's totally bizarro that Dell decided to invert the pins on the 12v pcie power connector)... works like a champ now :) the shakedown cruise has officially begun :p

I need to go get some JB Weld so I can mount the X51 PSU on the interior roof of the PC-Q02 (just welding the standoffs, not the actual power board, lol), then it will be a new set of custom wires and then I'll start snapping pix for a build/mod log :D

For right now it's going back into the same case, so it won't be any smaller... but it will have MUCH better cooling (and thus much quieter) by removing the SFX PSU / CPU heatsink sandwich! I need to talk to some folks about a new custom case (ahem, cmadki :p)
 
cool, man. are you replacing the cpu hsf with a bigger one or just giving the same one more room to breathe?
 
ekuest said:
cool, man. are you replacing the cpu hsf with a bigger one or just giving the same one more room to breathe?
Click to expand...

I might, with the new setup this could fit an AXP-140. I'm pretty happy with the AXP-100, though -- especially since I swapped out the thin 120mm fan for a full-thickness one (more cfm and less noise).
 
Incidentally, the pcie-power cable that comes with the x51 has custom low-profile 90-degree 6-pin connectors... i would love to find a source for these (and their 8-pin variants)!

low_profile_pcie_zpsf5128740.jpg
 
I'm curious what the brick you purchased pulls from the wall when it's not hooked up to anything, just sitting idle. I've never measured once but I've always imagined that power bricks eat up more power when off than standard PC PSUs.

Thoughts?
 
I built a sff pc with the alienware powerboard, too. My external AC-DC PSU will arrive in 2 weeks, so couldn't test it now. Could it be, that my PCIe-Plugs are also wrong pinned?
 
Machupo said:
Incidentally, the pcie-power cable that comes with the x51 has custom low-profile 90-degree 6-pin connectors... i would love to find a source for these (and their 8-pin variants)!

low_profile_pcie_zpsf5128740.jpg
Click to expand...

I'd like to know the source as well :)
 
Hey, I bought an x51 case but there is no 24-pin male to male connector. I want to make one myself, do you know how to?
 
After coming into possession of a new X51 myself, I'm curious if anyone around has done any PSU modifications with regard to cooling via heatsinks and maybe a large fan?
 
I have added some of the enzotech copper heatsinks and swapped out the 40mm fan for a noiseblocker version, but that was just for piece of mind while running it at it's max :)

It also runs just fine at max output (for extended sessions) without the fan (with heatsinks) ;)
 
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