Question VEGA 56 won't POST

[Wouated]

Hello,
I've just bought an AREZ RadeonRXVEGA56 to replace my old HD7850 but i'm having a hard time booting my computer. The situation is :
-If I only plug the VEGA56, the "VGA led" on my motherboard remains ON and nothing happend
-Pluging both my old and new GPU (old one in "first position") made my computer boot once, I opened the device manager and at the exact second "Radeon RX" apperead, screen froze for a few seconds and then blackscreen. Now, I always have a blackscreen just after the windows logo

Does any of you has an idea to solve this problem ?
Thanks

 

[Dark Lord of Tech]

Specs?

 

[King_V]

What are the full specs of your system?

 

[Wouated]

Motherboard : asus P7P55D
CPU : intel core i7 870
PSU : bequiet PurePower 10 700 W
GPU (old) Saphire HD7850 2G
GPU (new) Arez RXVEGA56 OC 8GB
3HDD
1SSD

 

[Dark Lord of Tech]

BIOS Current?

 

[Wouated]

American Megatrends inc. 0606, 03/09/2009

Thanks

 

[Dark Lord of Tech]

I seriously doubt that board will be compatible with that card. I have had to other posts with that chipset and a 2000 series card and they would not run the cards. A lot of pre 2012 setups won't run the newer cards.

 

[Wouated]

Ohhhh,
So the only solution for my problem is to change the motherboard ? (And the CPU I guess)
How to be sure that this new motherboard will be compatible with the GPU ? (Beside PCI-E 3.0)

Thanks a lot for your help

 

[King_V]

I believe that newer AMD cards won't work with older motherboards - I know specifically with older Dell PCs, some of the R9 and all of the RX cards have the issue where they don't support, I think it's VESA model 103, so can't even get to the BIOS.

I'm not sure if that specific issue is particular to Dells, or if it's an issue with any/all systems which are that old.

Pretty much anything fairly modern should work. My R9 285 for example, wouldn't work on a Sandy Bridge (2nd gen) equipped Dell, but works fine on my Haswell (4th gen) Dell.