Assistance Requested - Shutdown during BIOS

[Freewater]

I've recently assembled my first home-built, with the following specs:

Motherboard: nVidia 650i
CPU: Intel Core 2 Duo 2.66 GHz
GPU: e-GeForce 8800GTS 320MB

I've two sticks of RAM (1.9V, DDR2 800), a generic HDD on SATA, and a generic DVD-R/CD-R on SATA.

I've a LEXA NZXT case, which has 1x120mm, 2x120mm LED, & 1x80mm fans.
Deciding it would be a good idea, I went for a NZXT PSU - the PP500 (NZXT PP500)

The machine starts up, can access BIOS and what-not, but shuts itself down completely after about 60 seconds. I speculate the PSU is inadequate, and hence I come here asking for help.

The GPU asks for a minimum 400W PSU, with a +12V @ minimum 26A.
If I got the split rail bit correct, my PP500 with +12V @ 16A/17A with combined wattage at 396W, the amps should be adequate (396W / 12V = 33A > 26A).
Unless, of course, I've failed to absorb everything I've read in the past two hours.

Is this PSU supposed to be adequate?
What PSU, reasonably priced ($60-90), would work with this system?

Many thanks,

Freewater

 

[Dahak]

That would be the minimum required psu.Try going with something a little more stout,say around the 600watt range with 50amps on the 12volt rail.Also recheck all your connections again thoroughly.Make sure every cable and power connection is secure along with all cards(video/tv).Then check to make sure you have your f-panel connected correctly.Also check to make sure the power supply is set for your countries usage.I.E.220volt or 110-115volt.Sometimes these switches get knocked and then the psu won't work corrctly if at all.Goodluck.

Dahak

AMD X2 5600+ @ 2.8ghz(stock)
M2N32-SLI DELUXE MB
2 GIGS DDR2 800 RAM
THERMALTAKE 850WATT PSU
7950 GX2 560/1450
ACER 22IN. LCD
SMILIDON RAIDMAX GAMING CASE
80GIG/250gig SATA2 HD's
XP MCE
3DMARK05 14644

 

[Freewater]

Aye, I think I'm going to make a trip to Fry's tomorrow to look for a better PSU. Thanks for the numbers, Dahak.

I've double-checked all my power connections, and card/board connections - everything is in order.
Front panel bits are all A-OK, including the temp sensors.
Same with fans.

PSU switch is set to 110-115V.

Now, when EVGA told me they needed a minimum 400W PSU, did they mean PSU total, or on the combined 12V rail? Because I took it as PSU total wattage.

-Freewater

 

[Dahak]

That would be the absolute minimum psu that is required to run a basic system with that video card.As I've said before,i would go with a bigger and better psu.Always go with 25% more power for a psu than what system recommends for minimum.In this way you are assured of good power that allows for upgraging.Try THERMALTAKE for psu they are very good and built of high quality components.Goodluck.

Dahak

AMD X2 5600+ @ 2.8ghz(stock)
M2N32-SLI DELUXE MB
2 GIGS DDR2 800 RAM
THERMALTAKE 850WATT PSU
7950 GX2 560/1450
ACER 22IN. LCD
SMILIDON RAIDMAX GAMING CASE
80GIG/250gig SATA2 HD's
XP MCE
3DMARK05 14644

 

[Freewater]

I'm going to go for the Corsair HX620W - it should supply the power I'll need, and I suppose the added cost is worth it...
Combined wattage on 12V rails is 600W, giving 50A.

I'm also swapping out my NZXT Lexa case with the Antec P180 - it means dismantling my entire machine and keeping the components in storage for a few extra days only to re-assemble again, though, but that shouldn't be anything more than a minor inconvenience.
I am, however, concerned over stretching the 12V aux from the bottom of the Antec P180 to the upper left of my motherboard - the guys over at Silent PC Review had to stretch their cable over the PCI slots and barely connected.

 

[mlek]

You've probably done this already, but check the hsf seating. It could be shutting down due to overheating.

 

[Freewater]

Friend of mine suggested the same about an hour ago.
Lexa comes with heat sensors, and I've got one right over the hsf, letting me quantitatively address this possibility:
The maximum temp reading I've seen is 31C, and the entire rig first shut down at barely above room temperature (27C) on the first boot into BIOS. Ambient temperature has been 25C, and I've tried running the system open-air without a side panel with same results.
Upon unplugging a couple fans, the rig would stay on for a little longer, at roughly 60-90 seconds.
Because of this, I figured it couldn't be an overheating problem - assuming that the heat sensors work properly and my placement gives adequate readings (on the stationary CPU fan casing, right over the axle).

 

[TheRodent]

That wont tell you anything if there is a poor contact between the CPU and heatsink as occurs frequently with the 775 sockets. Its the temperature reported by the thermal diode on the CPU that is important, and could cause the board to shut down. The bios should have a screen reporting CPU temperature ( sometimes inaccurate ). Also i have heard that some boards have an option to shut down if the CPU fan is not detected.

As for PSUs the current rating for 12V is what you need to check. If it is insufficient it is likely that this will show up as a voltage drop under load - bios should have a screen for that but of course no load conditions.

 

[Freewater]

I jostled the HSF and made sure everything was in solid contact with the board, and checked the BIOS listed temperature for the CPU.
Bottom line, yes it was overheating - the thing stabilized out at 46C (by BIOS) and kept going without instant shut-down. I moved my heat sensor to better reflect the truer reading.

I'm still keen on getting the Corsair HX620W, though.

Thanks for the help, everybody.

Freewater out.