Need help... GPU very low benchmark scores... my MSI Board the bottleneck?

Question

Both the GPU is on a default clock speed.
Things I also notice
    During benchmark or gaming, GPU2 is 15c hotter
    I experience some glitches during gaming, like in Far Cry 3 the NPC movement goes retarded SOMETIMES (for example when they try to do something, their animation gets glitched and its like they are moving back and forth ultra fast) - have only played the game for 30mins but I could see this happen to NPCs.
    Also in Crysis 2 and Assassin's Creed 3, sometimes the graphics goes retarded like in AC3 the walls and the characters gets rumbled up while in Crysis 2 the graphics gets some artifact - The problem gets solve if I restart the game. It happens sometimes.
Well I just disabled SLI and tried another benchmark on each card (moving my monitor cable to each GPU)
Each card averages around 980 Score at Heaven. Ultra Quality and Extreme Tessel at 1080p 8xAA. And I think this is kinda low? Because I saw other people have around 1300 iirc.
Right now while Heaven is still at the background
GPU2 TOP
Graphics  405 MHz
Memory 324 MHz
Temp 45c
GPU1 BOTTOM (Testing this GPU)
Graphics 1306 MHz
Memory 3505 MHz
Temp 72c
When I tested GPU2 TOP the results are similar except I think GPU1 is around 38c
Please help me out, what should I do?
I'm thinking maybe my motherboard is bottlenecking my GPUs? I have OC Genie ON at 4.2Ghz. Using both GPU on the native x16 slots (base on the manual).
Please help.

Answer 1

Sometimes a reflash can straighten things out. Recommend to reflash using M-Flash BIOS + ME option with the archive given here;
https://forum-en.msi.com/index.php?topic=169796.msg1253345#msg1253345
Re-install the ME driver after the flash.
What does GPU-Z show for GPU1 and GPU2 for bandwidth? Recommend to place the cooler running card closest to the CPU when running SLI.
Have you tried each card individually in the PCI-E5 slot as well as in the PCI-E1 slot? If in PCI-E5 both run fine at 8X with no issues noted, you might try another SLI bridge.
With a Z68 and 2700k, GTX 480's (reference) in Gen2 SLI, 1920X1080, 47X, 1866 RAM, Heaven 4.0 test was 1604, Valley was 2709. With GTX 680's in Gen2 (reference) installed, Heaven was 2554, Valley 4674. There is definately something wrong if those GTX 480's were beating out your GTX 770's.
Added: Just ran another test;