My computer restarts when I play 3D games

Ok so I have a new computer that i built and it worked fine before my PSU 750 watt cooler master 700B "blew up" then i got this new Ultra X3 850 watt PSU and now when i play games after like 1-3 min of play my comp just restarts i tried turning off SLI but that wasn't it so now im stuck im quite computer savvy so ive tried everything i know to fix it on the software side but i don't know if it could be a hardware problem i know the prob is not overheating it could be some f-d up driver problem that i don't know about but any way here are my specs

DxDiag
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System Information
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Time of this report: 9/17/2009, 13:07:33
Machine name: ZEROXOZ
Operating System: Windows 7 Ultimate 64-bit (6.1, Build 7100) (7100.winmain_win7rc.090421-1700)
Language: English (Regional Setting: English)
System Manufacturer: INTEL_
System Model: DX58SO__
BIOS: Default System BIOS
Processor: Intel(R) Core(TM) i7 CPU 920 @ 2.67GHz (8 CPUs), ~2.7GHz
Memory: 6144MB RAM
Available OS Memory: 6132MB RAM
Page File: 5545MB used, 6715MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7100.0000 64bit Unicode

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DxDiag Notes
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Display Tab 1: No problems found.
Sound Tab 1: No problems found.
Sound Tab 2: No problems found.
Sound Tab 3: No problems found.
Input Tab: No problems found.

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DirectX Debug Levels
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Direct3D: 0/4 (retail)
DirectDraw: 0/4 (retail)
DirectInput: 0/5 (retail)
DirectMusic: 0/5 (retail)
DirectPlay: 0/9 (retail)
DirectSound: 0/5 (retail)
DirectShow: 0/6 (retail)

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Display Devices (i have dual)
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Card name: NVIDIA GeForce GTX 260
Manufacturer: NVIDIA
Chip type: NVxx
DAC type: Integrated RAMDAC
Device Key: Enum\PCI\VEN_10DE&DEV_05E2&SUBSYS_12623842&REV_A1
Display Memory: 3689 MB
Dedicated Memory: 879 MB
Shared Memory: 2809 MB
Current Mode: 1920 x 1080 (32 bit) (60Hz)
Monitor Name: Generic PnP Monitor

my motherboard is intel extreme DX58SO

what do u mean 1 or two vga? but to answer u my gfx cards sulply me with 4 seperate dvi and the last cooler master i got sucked as i explained and after it blew up i started to have these probs

ya ive dLd like all possible programs and put a thermometer in there just to be absolutly shure

btw i read this other post with same prob this guy had his GPUs on 6-pin to 6-pin PCI-E then he swaped that for a 6-pin PCI-E to split 4-pin molex and that fixed it so i tried that and it no longer shutdown and restarted it just froze. there are like two evenly spaced flickers 5 secs apart then small freze then perma freze if i close the game before the big freze there is no big freze which is interesting but other games still do the shutdown such as TF2 and LOL and HON lol and hon take a while to do that tho like say 5 min after a game is joined
(the game that im using for the bench mark for this problem is demigod )

A reboot during 3D games sounds like PSU problems.

If it was my own machine 1st thing I would try would be a new PSU, the problem you are having seems concurrent with not having enough ampage output to the pci-e rails connected to the VGA cards.

Other than that try testing / replacing your ram maybe, have had a few machines I have fixed with similar issues and that was always the 2 main problems.

try taking one of the GFX's out,then the other,see if the problom presists,see if the problom is solved..
it was'nt really clear,how are your graphic cards connected to the PSU again?