I seem to have a problem that has plagued all too many people that have purchased 4870 based cards. I love the card and I'm quite happy with how it has performed but now it is randomly crashing the entire system and the most maddening part is that the same set of situations will not always cause it to crash. Sometimes I'll be playing a 3D game like EVE Online or Prototype and the card will crashing bringing the rest of the system with it. Other times I'll simply be doing some web surfing and have some other 2D applications open and the card will crash taking the system with it. What happens when these crashes occur is that the video card stops sending a signal to my monitor and if there happens to be any sound playing it keeps looping. In order to get back to a working system I have to press the power button on the front of the case. When I get the system back up unfortunately there's nothing in the Windows logs to indicate precisely what has happened. So here's some additional information that perhaps you folks can use to help me out.
System Specifications
CPU: Intel Core 2 Duo E7400
Motherboard: Gigabyte GA-EP43-UD3L rev 1.0
RAM: 4GB of OCZ Gold DDR2-800 and 4GB of Kingston HyperX DDR2-1066 (they both have the same timings, the Kingston has to be overclocked in BIOS to run at 1066, it's going off SPD data currently as is the OCZ)
Video Card: Asus Dark Knight TOP Radeon 4870 512MB DDR5
HDD: Western Digital Caviar Black 640GB
HDD: Seagate 7200.11 1TB
DVD Burner: Lite On 24x DVD+/-RW
What I have tried so far:
1) Loaded various drivers for the video card. Currently I'm running the 10.7 drivers. I have also tried Catalyst 10.6, 10.5, 10.2, 10.1, and various other previous drivers
2) I have updated the motherboard BIOS to version F8, there is version F9 but all that supposedly does is fix a crossfire issue so I doubt it would help anything
3) I have updated all motherboard based drivers (network, audio and chipset)
4) I have replaced the previous PSU with a BFG GX-550 (the equivalent of a GS-550 except it is modular, the previous PSU is a GS-550)
5) I have stressed the video card using various games and tools to see if it will overheat and crash. I have tried Far Cry in demo loop with max details and 1920x1080 resolution for 10 hours during which the card never crashed. The same can be said for EVE Online as well. The card typically idles at about 61 degrees Celsius and the most I can push it to while gaming is around 84 to 86 degrees Celsius for the GPU. The memory portion of the card typically gets to a max of about 86 to 88 degrees Celsius and the Shader Core around 74 degrees Celsius. These temps were obtained using GPU-Z.
6) I have tested the RAM with both memtest86+ (latest version) and Microsoft's Memory Diagnostic. The RAM has passed running for 9 hours with 5 passes and 0 errors under memtest86+. Microsoft's memory test also was not able to find any errors.
7) I have stress tested the CPU using Prime95 for about 4 hours. During that time the CPU was under full load and it never got above 62 degrees Celsius. Most of the time it was going back and forth between 58 and 60 degrees Celsius which isn't bad for the OEM heatsink/fan that came with the CPU.

Every time the card crashes LEDs DE1602 and D601 as being lit.
9) I have checked to make sure all of my RAM is seated firmly and I've also made sure the video card is seated firmly by completely reseating all of my RAM and the video card. I've also made sure that the plugs going to the video card were in firmly. And while I was reseating everything I did my monthly cleaning of the card using a can of compressed air.
10) I have my PC plugged into an APC XS800 UPS which provides good clean power to the PC.
12) If I try and reboot just by pressing the reset button on the front of the case when this occurs it will reboot without video and do the Award BIOS beep sequence of long-short-short. If I have to use the reset button for any other reason it works normally. In order to get video after this issue occurs I have to hold down the power button to completely shut off the system and then press it again to turn power back on.
I'm seeking this second opinion because after looking through various websites reviews on the BFG GX-550 PSU that I have seem to be mixed. The PSU is essentially the same as the BFG GS-550 except it is modular. Both are supposedly manufactured by Huntkey and while some folks say its a good PSU others say its not so great. So, is there a reasonably good chance that if I replace the PSU with something like a Corsair or Antec PSU my problems will be taken care of or is it more likely that there is something wrong with my video card?