Asus Maximus V Extreme not offering enough power to USB 3.0 ports

[ktfzone]

Hi all,

I have the following setup :

Asus Maximus V Extreme
Intel 2600k + Noctua D14
32 gb RAM @ 1333 Mhz
2 * Asus Radeon 280x in Crossfire
one Sil PCIe SATA controller
one combo network / audio card, Asus Thunderbolt, which came in a bundle with a Rampage III Black Edition
PSU Corsair AX750
9 HDDs, 2tb and 3tb each and a 240gb SSD.


Other than the vents from the CPU, no other vent connected to the motherboard. The issue that I have is with external hard drives, they are not recognized. And I am talking here about 2.5" drives, which should not take that much current.

After many tests, I realized that :
- the HDD doesn't have the current to start, it keeps clicking trying to start;
- I tried all the ports from the back, the ONLY one that works is the ROG Connect one, which is a USB 2.0 sadly
- I connected the internal USB to the case (a Nanoxia Deep Silence 6) , no luck there either.
- the funny part is that when I connect my Dell 2412m monitor to an USB from the back and connect the HDD to the monitor, it works. The same port, if I use the drive directly in it, doesn't work.

I tried connecting the EZ Plug 2 with a FDD power cable, made no difference. What am I missing here ?

[Myk_SilentShado]

You are most probably pushing your PSU too hard, you've got 2 high end VGA's drawing power from a 750W PSU, you should ideally be using a minimum 850W PSU.

[ktfzone]

I am running the entire PC on 1000va UPS from APC and it never goes close to 90% , which is less than 700 W. On regular desktop work, it stays at ~40%, which should be more than enough. I will have to test with different PSU, but I want to make sure I am testing all other possible causes first.

The thing is ... the computer is rock solid in anything else (after tweaking those damn 280x to stop entering in ULPS mode and so on ) , it's just the USB 3.0 thingie that drives me crazy.

[Highlnder3]

ktfzone wrote:
I am running the entire PC on 1000va UPS from APC and it never goes close to 90% , which is less than 700 W. On regular desktop work, it stays at ~40%, which should be more than enough. I will have to test with different PSU, but I want to make sure I am testing all other possible causes first.

The thing is ... the computer is rock solid in anything else (after tweaking those damn 280x to stop entering in ULPS mode and so on ) , it's just the USB 3.0 thingie that drives me crazy.

The UPS doesn't matter, your PSU does. How old is your UPS? They do go bad.

Not only do you have 2 high end GPUs, you also have 9 HDDs and a SSD!!! Get yourself a beefier PSU. Also I have to ask, are you sure the external enclosure(s) are USB 3.0? If you try to plug in a 2.0 in a 3.0 port you will have problems.

[ktfzone]

The PSU is 4 years old and it was the top of the line of Corsair's gold line. The external enclosure is USB 3.0, tested on a different PC. And besides... it doesn't work in any USB 2.0 port either, not enough power to start the HDD (which is a lame laptop HDD, 2.5", 160gb).

[Highlnder3]

ktfzone wrote:
The PSU is 4 years old and it was the top of the line of Corsair's gold line. The external enclosure is USB 3.0, tested on a different PC. And besides... it doesn't work in any USB 2.0 port either, not enough power to start the HDD (which is a lame laptop HDD, 2.5", 160gb).

I only asked if the enclosure was USB3.0 to make sure. Regardless of how old the PSU is or how great it was when it was new, you don't have enough power for all that you're running. Do yourself a favor, find someone to lend you a 1k PSU or larger and see what happens then.

[ktfzone]

I removed the sound card and one of the video cards. I updated BIOS to the latest version and tested again. No change. There should be no issues with power with just one card on that PSU.

[Highlnder3]

ktfzone wrote:
I removed the sound card and one of the video cards. I updated BIOS to the latest version and tested again. No change. There should be no issues with power with just one card on that PSU.

That is a good test, however, what if that PSU is bad? I still suggest that you try a different PSU, your call.

[billyray520]

I have 1200 W PSU and never had problems with the USB 3.0 ports. However, I would concentrate on your USB 3.0 connections first. Have your USB 3.0 connectors EVER worked, or is this something new? Do you have the drivers installed correctly? Does you Device Manager show USB 3.0 ports? (I'm assuming Windows 7)