is 700W enough power?

[jthunderloc]

Hello all, I've been having some problems recently with random shut offs while playing BF:BC2

Current setup
i5-750 OC with a very slight voltage increase, turbo mode, C State and EIST enabled.
EVGA P55 FTW
2x 4890s Overclocked to 925/1050
1X Sata HDD
2X IDE HDD using SATA/IDE adapters
2X sticks corsair DDR 3 1600
7 fans (1 80 4 120s, 2 200)
1x LED 92MM Cpu cooler
2x LED GPU coolers (80 or 92mm)
running off of a OCZ StealthXStream 700W power supply.

Problem -
Random shut downs only occuring while playing Bad Company 2, do not seem to happen with any predictability. I've had it happen after 5 minutes and after 3 hours. Computer immediately reboots and loads windows and acts like nothing happened. I added an 80mm fan blowing into the rear of the OCZ to keep things cool.

I'm currently stress testing each component to make certain which item is acting up. using the Antec power supply calculator it told me 500w would be enough, the OCZ is rated at 700W continuous. I'm starting to wonder if I need more power or if my unit is acting up. OCZ unit was purchased in December and has only seen 2 months of use so its still under warranty.

I had the unit tested a while back and it tested fine (verifying GPU failed, and not another component) Only 3 weeks of use since testing. If I run a single card in any of the slots on the FTW it handles 20min of FURmark with no issues, if I run both cards the system shuts off and reboots after only 3.

-Wes

 

[Mr. Pedantic]

I would say that 700W would be pushing it. Even at stock a 4890 uses over 200W at Furmark load, which leaves just over 200W for an OC'ed 750, mobo, HDDs, RAM, and fans. I'd say that's a bit tight.

So you only took out one of the GPUs? If so, alternate out the other as well to make sure that it's not the first GPU that's causing the trouble.

 

[Stefan Payne]

If the i5/750 uses 200W than the least of his problems is the PSU.

Anyway: is your memory OK, have you tried without OC?

 

[Mr. Pedantic]

If the i5/750 uses 200W than the least of his problems is the PSU.

He has other components in his PC as well, including a motherboard, 3 hard drives, and 7 fans. All together they take up quite a bit of power too.

Also, I'd say 500W is a conservative estimate of total power draw of 2 4890s during Furmark load.

 

[fffblackmage]

Take a 4890 out. If you stop having problems, then you'd know it's the PSU. Or it's a heat related issue, though I'm guessing that unlikely...

 

[jthunderloc]

I stress tested each GPU individually, in all 3 PCI slots on the FTW and no problems what so ever. Currently I have the GPUs and 1 HDD hooked up to an AMD Phenom II 955 chip on an MSI 890GXM board to see if its a Mobo/CPU issue. 15 minutes of Furmark and no problems.

I have the same setup chip clock as tomshardware did in this guide, my 750 should be pulling around 165 at full load. the CPU has been thourghly stress tested and has had no problems.

memory has passed memtest on several passes and is A-OK.

I dont really care for testing with furmark, it stresses the system far more then normal use would but it recreates my problem in a very predictable manner. the 955, from what benchmarks show, draws more power then the 750 would (243w at load) I could very easily be reading these wrong or misinterpreting them.

I'm going to pick up a different PS tomorrow for testing purposes and a kill-a-watt to see what kind of juice is being pulled from the wall to get a better idea of whats going on.

-Wes

 

[BTRY B 529th FA BN]

Could either be a driver or your RAM. Memtest86 may pass numerous times and still be bad. I'd suggest Memtest HCI & also LinX. If you can't pass LinX, i'd loosen the timings and downclock the ram. Run it at 1333 or lower, loosen the timings, and put the ram at it's specified voltages. Then try LinX again.

 

[jthunderloc]

I suspected the drives first and get the same results on catalyst 9.12, 10.2 and10.3 even after a fresh install of Windows 7 64. I'll try memtest hci, memeory is running at its rated specs. CPU stability testing was done with 20 passes of Linx at all multipliers, 60 passes total.

-Wes

 

[jthunderloc]

Alright, heres where I sit now.

I've tested both GPUs in crossfire with the Phenom II 955, which by all accounts should draw considerably more power then the i5-750. ran just fine, temps were on the low side (peak around 73 furmark dual GPU test) Performed a memory test using Memtest HCI and everything checked out. Reinstalled everything back into the case (HAF 922) and restored everything to its default settings. unplugged everything that wasnt vital to testing (2X GPU, 2X RAM, CPU cooler, and 1 HDD) sat a high power fan outside of the case and cranked it up to get airflow and fired up furmark. 6 minutes in I grew hopefull that it was just an unstable overclock and that I had found a solution that didnt need any new parts. Nope, powered down and rebooted, I've run it 3 times and it fails predictably between 6 and 7 minutes. GPU temps are on the high side, around 86*. Normal GPU temps are in the mid 50s while gaming and the problem still occurs so I cant imagine its a temp issue.

I'm fairly certain the problem lies in either the Motherboard or the Power supply as every other component, aside from the CPU, has been tested rigorously outside this setup and performed great. the CPU has been tested rigorously inside this setup and never caused the reboot issue so I am extremely doubtful its the problem.

It feels like I'm on the right track here, but I'm a bit inexperienced with all this, and figure testing everything like crazy will make up for it. Does it sound like I'm heading in the right direction or walking down the wrong path?

Thanks!
-Wes

 

[theAnimal]

Also, I'd say 500W is a conservative estimate of total power draw of 2 4890s during Furmark load.

ht4u.net measured HD4870 @ 187.2W in furmark, so I'd say 500W is completely unrealistic especially considering the second card in SLI/CF uses less power than the first.

 

[BTRY B 529th FA BN]

That's the thing. Lower the Speed from 1600 to around 1333 and keep your voltage specs but loosen your timings. Memory can fail over time and is usually the culprit. I had a DDR2 1000 kit that would pass for hours sometimes over 10hrs and LinX would fail. I ran it at 400fsb (DDR2 800) and it still failed. I bought a new kit, ran it at 400fsb and it was perfect. this was the kit I bought and my Q9550 ran great; I know I sold a perfectly good Q9650 for cheap because I thought it was the chip: it was the ram.