GPU boots only using LEGACY ROM , and not the default EFI-compatible ROM. Why?

[deano145]

Using the BIOS it is possible to change the PCIe ROM from the default "EFI-compatible ROM" to the "Legacy ROM":

I started with integrated GPU (IGPU) to install Windows 7. After that, using EFI compatible ROM, there's no GPU display. ALL fans and lights work fine, except my USB keyboard numlock light no longer turns on. Then I switched to Legacy ROM and everything works fine. When I did this, initially, the dxdiag said:

• Name: Standard VGA graphics adapter
• Manufacturer: (Standard display types)
• Chip type: AMD ATOMBIOS
• DAC type: 8 bit

So my GPU was generically recognised now without drivers. Using IGPU, I installed the latest Catalyst software (13.2). I then switched to Legacy mode, and dxdiag almost correctly identified my GPU (e.g. said it was from the 7000 series with 4GB RAM, although it has 3GB RAM. In order to get the correct dxdiag I have to run the "64bit dxdiag diagnostic tool" everytime I open dxdiag).

Anyway, switching back to EFI, I got NO display once again even with the GPU drivers updated.

My mobo BIOS is F16, and newest ones are F18 or F19j(beta). I do not have this yet. I use HDMI cables. I do not have any other, but may buy some tomorrow (VGA/DVI).

My specs can be found here: http://pcpartpicker.com/p/1hejv but I will post them below anyway:

CPU: Intel Core i5-3570K 3.4GHz Quad-Core Processor  ($189.99 @ Microcenter)
Motherboard: Gigabyte GA-Z77-D3H ATX  LGA1155 Motherboard  ($109.99 @ Amazon)
Memory: G.Skill Ripjaws X Series 8GB (2 x 4GB) DDR3-1600 Memory  ($71.99 @ Newegg)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive  ($59.99 @ NCIX US)
Video Card: Gigabyte Radeon HD 7950 3GB Video Card  ($274.99 @ NCIX US)
Wireless Network Adapter: TP-Link TL-WN781ND 802.11b/g/n PCI Wi-Fi Adapter  ($14.99 @ Newegg)
Case: Zalman Z5 Plus ATX Mid Tower Case  ($45.99 @ Newegg)
Power Supply: XFX 550W 80 PLUS Bronze Certified ATX12V / EPS12V Power Supply  ($45.99 @ NCIX US)
Monitor: LG IPS224V-PN 21.5" Monitor  ($157.58 @ Newegg)

I need to use EFI-compatible ROM, so what should I do? I have just sent Gigabyte a form but I am not sure when they'll reply.

- I do not have any other parts nor friends nearby
- The GPU doesn't even work in the PCIx4 slot (I want it in the PCIx16 anyway) if EFI-compatible ROM is active

[JohnnyBigodes]

You wont get any response on these Forums for your problem.

I have somehow the same problem with my Gigabyte GTX 670.

I updated the GPU BIOS from F4 to F5 and my PC wont boot anymore if i have UEFI Boot mode activated.

With Legacy Mode the PC boots without a problem.

[adiiee]

You need to update your MB Bios to a newer version if available to boot in UEFI mode with the newer GPU's( Ex GTX 670 - It comes with a UEFI bios of it's own) or GPU's updated to newer BIOS having UEFI. Since you have already switched to UEFI mode in BIOS without the update and not able to enter the BIOS again, you need to put a older GPU which are legacy ROM based, flash the MB with the latest bios and then attempt to boot the system with UEFI mode for the PCIe ROM.

If there is no update available to you MB right now, then you have to stick with the legacy ROM option.