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[Problem] UEFI card on a legacy BIOS Mobo!

Joined
May 17, 2017
Messages
109 (0.04/day)
System Name War Daddy
Processor Intel Core i7-950 @4.1GHz
Motherboard ASUS SABERTOOTH X58
Cooling Cryorig R1
Memory 3x4GB SAMSUNG DDR3 1600MHz
Video Card(s) SAPPHIRE NITRO+ RX 570 8GB
Storage Segate barcuda 2TB
Display(s) SAMSUNG S24C750
Case Corsair carbide spec 03
Power Supply EVGA G3 650W
Hi, Guys! I've just bought an used Rx460 4GB but it acts very strange! the BIOS became choppy as if it's running @ <20 fps! Also windows sometimes takes ages to load and sometimes it won't boot at all (flashing black screen or stuck at windows logo) but when I managed to boot I didn't face any problems, I even have run heaven benchmark for an hour with no problems.

I've noticed that Rx series only supports uefi and I have ASUS P5Q-E which uses legacy BIOS. Is that the problem? Or I've got a faulty Card?

It's also worth mentioning that my previous card was a faulty 7970 which I used to bake it at oven but the last time it gave me black screen, no post, no beep and numlock off! I had to fully reset the BIOS (removed the battery and set the jumper to clrcmos) and the pc didn't post until I removed 24-pins cable and cpu power cable for a couple of minutes then put them back.

So do you think it's uefi-legacy bios problem or did my 7970 short the mobo and cause damage to the pci-e?
 

Here, same GPU, P55 board with AMI BIOS.

Note: This was filmed on the first boot since i put the GPU in my rig.
 
I had my Vega 64 running like a champ in an EVGA x58 board, no problems, no special settings.
 
Hi, Guys! I've just bought an used Rx460 4GB but it acts very strange! the BIOS became choppy as if it's running @ <20 fps! Also windows sometimes takes ages to load and sometimes it won't boot at all (flashing black screen or stuck at windows logo) but when I managed to boot I didn't face any problems, I even have run heaven benchmark for an hour with no problems.

I've noticed that Rx series only supports uefi and I have ASUS P5Q-E which uses legacy BIOS. Is that the problem? Or I've got a faulty Card?

It's also worth mentioning that my previous card was a faulty 7970 which I used to bake it at oven but the last time it gave me black screen, no post, no beep and numlock off! I had to fully reset the BIOS (removed the battery and set the jumper to clrcmos) and the pc didn't post until I removed 24-pins cable and cpu power cable for a couple of minutes then put them back.

So do you think it's uefi-legacy bios problem or did my 7970 short the mobo and cause damage to the pci-e?

AFAIK, almost all UEFI video cards have hybrid BIOSes so they will work with either UEFI or legacy motherboards. If it was a UEFI only card, then it wouldn't even boot in a legacy BIOS motherboard.
 
Exactly as @newtekie1 said. If the problem was incompatibility with the BIOs mode, it would never even boot. Unfortunately, something bad might have happened with the mobo when the 7970 died on it.
 

Here, same GPU, P55 board with AMI BIOS.

Note: This was filmed on the first boot since i put the GPU in my rig.

OT, but is that the Samsung 26" TV/Monitor? 1920x1200 resolution? If so I have the same screen, it's quite nice. The power saving is non-existent for PC connections though, it never goes to sleep despite the energy saving logo on it
 
I cant say about AMD cards but running a GTX 1080 TI on a X58 board that dosent have UEFI and that works great. Based on that, it more sounds to me that you have a faulty card. Just to be sure, is there any change if you try a another PCIe port?
 
Sorry for the long silence and thanks guys for your concern and your helpful inputs.

Here, same GPU, P55 board with AMI BIOS.

Note: This was filmed on the first boot since i put the GPU in my rig.
I had my Vega 64 running like a champ in an EVGA x58 board, no problems, no special settings.
Both of those motherboards are newer than mine which is lga775 so maybe you got better BIOS support!
AFAIK, almost all UEFI video cards have hybrid BIOSes so they will work with either UEFI or legacy motherboards. If it was a UEFI only card, then it wouldn't even boot in a legacy BIOS motherboard.
That makes sense! But maybe my specific mobo and its specific BIOS is so old and not fully support and got some bugs!
I cant say about AMD cards but running a GTX 1080 TI on a X58 board that dosent have UEFI and that works great. Based on that, it more sounds to me that you have a faulty card. Just to be sure, is there any change if you try a another PCIe port?
Yeah I tried with the same results! If the 7970 damaged the primary slot, would that affect the other two slots as they get controlled all together via the southbridge? or they are supposed to work separately?
I have heard that specifically Sapphire RX cards has problems with Legacy BIOS.
Even some people from Sapphire know something isn't right.
Still, there is not very much info about this issue on the internet, because we are talking about Legacy BIOS...
Well, that gives some hope! I'm afraid that I got a faulty mobo as I can't afford upgrading the whole platform ATM but I'm going to try another gpu tomorrow and I will tell you what happened but I'm sure it's something related to the BIOS as after I managed to boot successfully it's running normal, Heaven has been running for a couple of hours with no problems!
 
I dont have video proof, but i tested the RX 460 i had on a P45 C51 as well and also it worked as expected.
You need to update the bios on that board.

Ill report back on tuesday if problem is not solved, since a friend is getting an RX 560 for his q6600 on a P5G41T-M LX2/GB
and ill post a video here as proof that 460/560 can work on older 775 mobos.
 
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I dont have video proof, but i tested the RX 460 i had on a P45 C51 as well and also it worked as expected.
You need to update the bios on that board.

Ill report back on tuesday if problem is not solved, since a friend is getting an RX 560 for his q6600 on a P5G41T-M LX2/GB
and ill post a video here as proof that 460/560 can work on older 775 mobos.
Thanks for your concern, I really appreciate that. But I think that the problem is laying in the gpu, today I baked my 7970 for the last time and it's working normally, bios was smooth although it crashed in windows. Another thing, when I was trying to enter the safe mode I get red vertical lines and tiny red dots flashing around but I didn't see that again after restart. What really confuses me that it's never crashed while gaming or stressing even with OC!
Anyway, I'm waiting for your report for purely academic purposes :D
 
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