I think I need a bigger PSU? pls advise

[Force_FeedR]

okay, so

here are the specs that I have, and running the Thermaltake 750W as per Thermaltakeusa*»*Power Supply*»*600W - 850W*»*Toughpower Standard 750W PSU : Toughpower Standard 750W PSU W0117RU

System Type: 1 physical CPU
Motherboard: High End - Desktop (lets assume the K9N2 sli is high end)
CPU Socket: Socket AM2+
CPU: AMD Phenom X4 9950 2600 MHz Agena
CPU Utilization (TDP): 90% TDP

RAM: 4 Sticks DDR2 SDRAM
Video Card 1: NVIDIA GeForce 8800 GTX
Video Card 2: NVIDIA GeForce 8800 GTX
Video Type: SLI

IDE HDD 5400 rpm: 1 HDD
Regular SATA: 1 HDD

DVD-RW/DVD+RW Drive:1 Drive
PCI-e x16 Card: 2 Cards
Fan Controller: Yes
Front Bay LCD Display: Yes

Fans
Regular: 1 Fan 140mm;
LED: 3 Fans 80mm; 3 Fans 120mm;

Cold Cathodes: 1 Cathode

Keyboard and mouse: Yes

System Load: 90 %


Minimum PSU Wattage: 642 Watts
Recommended Wattage:692 Watts


Is my TT 750w enough to power this system,

because I think I might have overloaded the system last night, had trouble loading IDE drives in bios, when I plugged some fans it went through, plugged them in and started having trouble again. removed 1x GTX and everything was fine.

also I want to ask is it possible to overload one specific rail?

 

[Oj0]

Not likely. When your system is idling in the BIOS your power draw is going to be under 200w. The cards aren't drawing their TDP until they're at 100% load, the same goes for your CPU. Your problem is more likely the Thermaltake badge on your PSU - a TT badge makes any PSU rubbish And yes, you can trigger the OCP (over current protection) on a single rail which will result in the PSU powering down.

 

[JollyJamma]

SLi and Xfire needs more Amperage than watts hey.

 

[Oj0]

Are you serious??? Wattage = amperage * voltage. You're working on the 12v rail so the rate at which amperage and wattage go up will be 1:1.

 

[Force_FeedR]

AHA!!

thanks for the feedback.

think im gonna have an excuse to rebuild the whole thing again, yipee!!

and then,

how much is my rig worth? two rand fifty ?

I'm thinking of getting rid of it, or maybe i should swop my RC for bigger psu and then sell it, or split it.....

 

[CyB3rThuG]

That PSU is more than enough for that setup !! Even with that SLI and all those fans

There is somewhere a power use calculator that can calculate ur watt, amps ect...

Sumthing like Power Supply Calculator
or
Computer Power Supply Calculator | Schrock Innovations Computer Company


There should be better ones tho.

 

[Force_FeedR]

@Stuartc

yes I used eXtreme PSU Calculator @ eXtreme Outer Vision - eXtreme tools for computer enthusiasts

That is why I was wondering if maybe I was getting to close to the limits.

 

[BillyBob]

PSU may be enough "in principle" - being a 750w unit, but it may very well be overloading a single rail, which causes everything to go to shambles... Also bear in mind that with capacitor ageing, that if one considers that the PSU may not be brand new, and having seen a fair bit of use, the rated 750W output of the PSU (and likewise the W / amp rating on a single offending rail) will have decreased over time - so a PSU / rail that was juuuust cutting a month ago, may have deteriorated to the point of no longer being up to par - especially if a rail's been pushed hard and to its rated limit as a regular occurrence.

I'd recommend getting a strong single-rail PSU to test with, and see if the issue persists.

 

[CyB3rThuG]

My setup before my new upgrade was a i5 760, sabertooth 55i, 2x 2g mem, gtx 460, 6 hdd's (1x500g, 2x1tb,1x1.5tb,2x2tb), 2x 80mm fans, 1x 120m fan
Done all that using a 650W CM power supply, and now Im still gona use it with my new rig, my gtx460 got 2 6 ping power plugs on it

@BillyBob
Agreed...

@Force_FeeR
The PSU may be running out of life, not as strong anymore

 

[chickenbeef]

My setup before my new upgrade was a i5 760, sabertooth 55i, 2x 2g mem, gtx 460, 6 hdd's (1x500g, 2x1tb,1x1.5tb,2x2tb), 2x 80mm fans, 1x 120m fan
Done all that using a 650W CM power supply, and now Im still gona use it with my new rig, my gtx460 got 2 6 ping power plugs on it

Well the OP does have a 140mm fan, those do take up a fair share of power.

 

[Force_FeedR]

@ Bawb,

Im gonna do a rebuild this weekend and see what the best way would be to do the setup, although last night when i was putting in the 2nd gtx, i was thinking to myself, if I had to run 4x6pin connections that = 8x molex. that sounds like a lot of power consumption.

I am currently running 1st GTX on straight 6pin and 8pin to 6pin conversion.
then on 2nd GTX I am running 2 6pins from the same molex rail and the fan controller with about 4 fans + the GTX aftermarket cooler.

I did run the aftermarket cooler on the molex rail that goes into the mobo (the mobo uses 1x 6pin "or 4pin" and 1x molex on the mobo itself) as well, but its connected to the HDD and DVD drive, and when I started it up it gave trouble.

whats the best way to do this setup?

 

[chickenbeef]

You should have it like this;

GPU1 - 8 pin from PSU with 6 pin adapter and molex -> 6 pin

GPU2 - 6 pin from PSU and molex (From a different string of molexs to the one used above as it should be on a different rail)-> 6 pin

 

[Force_FeedR]

You should have it like this;

GPU1 - 8 pin from PSU with 6 pin adapter and molex -> 6 pin

GPU2 - 6 pin from PSU and molex (From a different string of molexs to the one used above as it should be on a different rail)-> 6 pin

okay that sounds like a plan, I was thinking along those lines, but thanks for confirmation!!

 

[Oj0]

PSU may be enough "in principle" - being a 750w unit, but it may very well be overloading a single rail, which causes everything to go to shambles... Also bear in mind that with capacitor ageing, that if one considers that the PSU may not be brand new, and having seen a fair bit of use, the rated 750W output of the PSU (and likewise the W / amp rating on a single offending rail) will have decreased over time - so a PSU / rail that was juuuust cutting a month ago, may have deteriorated to the point of no longer being up to par - especially if a rail's been pushed hard and to its rated limit as a regular occurrence.

I'd recommend getting a strong single-rail PSU to test with, and see if the issue persists.

Bawb, I agree but he's having issues in the BIOS. The system is completely idle, if it's drawing more than 150w I'd be surprised.

Well the OP does have a 140mm fan, those do take up a fair share of power.

Troll.

 

[BillyBob]

Bawb, I agree but he's having issues in the BIOS. The system is completely idle, if it's drawing more than 150w I'd be surprised.

Missed the BIOS bit... still wouldn't rule out the PSU, considering that with a GTX removed, the issue is solved - but that could be a mobo issue as well.

First subject for elimination from the equation would have to be the PSU IMHO.

Otherwise, take the whole affair as a CUD motivator, tear it all down and rebuild a new system from scratch.

When in doubt, re-build!

 

[CyB3rThuG]

Yea but not to limit a 750W psu

 

[Force_FeedR]

the bios issue, let me explain what happens there.

so, I got the 2nd gtx, put it in to test, and it started up with a pink display on screen.
I took the card out and put in 1st gtx, everything was fine. put the 2nd gtx in again and used the other DVI plug, all was fine, started up installed and shutdown pc to initiate SLI.

so took out 2nd gtx, put it in bottom pcie and 1st gtx back where it was, plugs were arranged as previously posted. then proceeded to boot, and when it got to boot IDE drives it hindered and I could hear a feint hdd spin up/seek sound (you know that eerie sound you hear when ide drives fail they spin up and seek). I though okay I either overloaded something or something is unplugged, checked all the plugs, started up again, but this time before the screen could initiate I heard a "POP" accompanied by the Hdd spin/seek and I thought to myself, oh "hey soos" now its over, but the screen initiated dislpay and started up into windows without any issues. I dont know where the pop came from I smelt the PSu and it was fine.

The Bios issue was sorted out when I unplugged the cold cat and some fans. I did also at one stage switch off the fan LED's through the Scouts' front panel control, and they dont come back on now, but the fans spin because the fan and the led's get power from different sources. so now im wondering i maybe I blew something on the mobo, i will have to check tonight.

 

[CyB3rThuG]

That's actually a good idea, not to many connections on a single string may sort it out

When in doubt, re-build!