ST85ZF voltage regulation

[taemun]

I've had my ST85ZF for around 8 months now. It has treated me well (although I have managed to break two of the SATA connectors thanks to excessive hotswapping of drives :().

Recently (last two weeks) I've gotten an Abit IP35 Pro, and have noticed rather considerable undervolting of vCore under load (droop). I was rather surprised, considering that this board is reputed to have very good droop. 1.6V in BIOS leads to around 1.55~1.56V in Abit's uGuru tool and that drop to around 1.52V under load. CPU is an E6700 @ 3.8GHz, nothing too drastic. (as a side note, I'm inclined to agree with the voltages given by the motherboard for the vCore; as overclocking results from previous boards/vCores agree.)

I (for no reason in particular) hooked up my multimeter to a spare molex lead, yellow wire / black. 11.66V. o.0
ORTHOS or3DMark load -> 11.64. A both PCIe plug gave similar readings (within 0.02V consistently), as did the spare 6p (2xGND, 2x12V, 2x3.3V) plug. 5V is 4.97V, regardless of load. 3.3V is 3.31V.

My question(s):
Could my PSU's low (but within the published specs of 5% and well within the ATX specs of 10%) 12V rail be inducing the boards undervolting?
Should I be worried about the voltages (on at least 2 of the 4 12V rails)?

I have bought a G0 Q6600 and it should be arriving next week, and want something that will be running well for it to sit in.

It has just occurred to me that I have a spare Hiper Type-M 730W on hand, so I will swap that in tomorrow and see what it does.

Rig:
Silverstone ST85ZF (rev A1)
E6700 @ 3800
Abit IP35 Pro
8800GTX @ Ultra
1x 74G Raptor
5x various 7200rpm 3.5" drives
X-Fi EP (for enormous penis of course :))
Two optical drives

Thanks in advance for any responses :)
t

[Super Nade]

Does measurements at the 24 pin ATX connector give the same results?

11.66 on a 12V rail is not good.

[taemun]

Super Nade:
How should I measure the voltage on the 24p ATX plug whilst running? Or did you mean without load?

(I'd have responded earlier, but the forum went down, and didn't check back until now)

t

[Super Nade]

You can jam the multimeter probes in. :)

[taemun]

Yeah, with or without load the output is ~11.66V.

The Hiper 730W that I mentioned previously, it gives a fairly stable 11.90V. This undervolts around 0.2V less under load :(

(sad face because I can't keep the Hiper in service lol, it has to be returned to a friend soon)

Any suggestions? Should the Silverstone ST85ZF be warranty-able? From what I can see, the 12V is within "spec" and as such shouldn't really be able to be warrantied. :wall:

I find it a little odd that *all* of the +12V rails on the ST85ZF are ~11.66V. It isn't like they are being particularly taxed (as I said above, even without load its around the same!). Does this PSU have tweakable pots or anything?

Thanks,
t

[Super Nade]

11.66 is not good. Return it.

[Spectre]

11.66 is not good. Return it.

But it is in specifications...

[Super Nade]

But it is in specifications...

:)

[taemun]

Now is the point when I mention that it is about 11 months old :)

My old mobo didn't undervolt like this - and I never had a reason to look at the +12V voltage previously.

I live in Australia, and as such, everything computer parts wise is covered by at least a 12 month warranty, so that isn't a problem from that perspective. More that I doubt that the retailer will want to warranty something that is "within spec" after 11 months :(

[15 mins later] Hell the disty for them here (Altech) lists the warranty period as:
Warranty :
3-year Manufact.

Worth a shot I guess.

Cheers,
t

[signmeuptoo]

Just don't tell them it is within "spec" but that it is giving your computer problems, such as "xxxxx" and let them deal with it. You have the right to a good product when you pay a lot of money.

[Spectre]

But the product is in spec (ergo good)..........and the PSU hasn't changed. Normally when you change a component and have an issue you look at what has changed first.