Flashing BIOS to different PCB cards

[shogun]

Hi, I have a SLI setup 9800gtx+ cards. One's from Asus and the other one is from PNY. They run at 1.2V and 1.3V, which makes them go very very hot (temperatures are also very high at south Spain where I live). The Asus ones reaches 74/75ºC very easily when full charge and the PNY goes till 83ºC. To solve the high temps problem I have thought about flashing them with the EVGA SC BIOS (I can't find the SSC one) or the MSI OC BIOS, both running at 1.15V. The problem is that my cards have different PCBs. The Asus is the first revision with the large PCB and two 6-pin power connectors (Device ID 0612), and the PNY has the new and smaller PCB with just one 6-pin power connector, similar to the GTS250 and with Device ID 0613.

Then, my question is: can I flash both cards with the same BIOS or will one of the cards break down? PCB is different, but so are different GTS250 and 9800gtx+ PCBs and I have read about many people flashing GTS250 BIOS to 9800gtx+ cards in order to get SLI working, so I'm not sure about what to do.

Secondly, if I finally decide to flash them, do I need to flash each card separately or can I flash both cards while in SLI mode?

 

[INSTG8R]

Never a good idea flashing BIOS's from other cards and even more so when they are different PCB/models.
A better idea would be to dump the BIOS's from your cards and edit them to the clocks/voltages you are after then reflash the cards. Then you are still using the cards original BIOS.

 

[shogun]

Well, I wanted to use an official manufacturer BIOS because they're specs are supposed to be tested and stable, since I can't test the OC with the different voltages (my card generation has voltage control locked). And with those temps, I want to flash them for sure. I've been taking a look at the dumped BIOS and while Asus says the risk temperature is 82ºC, PNY says it's 105ºC

Well, that said, should I understand that the best then is to copy the, for example, EVGA specs to the dumped BIOS and flash separately each modified BIOS in it's respective card?