HP 6300 Pro MT with ASUS R9 285 Strix - Desperately need help

[DeepRed]

Hi,

Please bear with me through this long post because I tried to give as much detail as possible hoping that someone can be of help. For some 10-15 days I've been desperately trying to figure out how to integrate my ASUS R9 285 strix GPU into my HP 6300 Pro MT.

Since the chassis and motherboard layout is not built for such a GPU + the internal PSU is of 320 Watts, I'm trying a very strange thing.

I bought 1 additional PSU and I already had had 1 another. So basically I'm feeding the GPU with 2 external PSU's.
Since the GPU does not fit inside (because of CPU and its fan is blocking the way), I used a 16x-16x Pin PCIE cable.
Everything is fine in theory.

The problem is, whatever I do, I couldn't manage the computer to run with this GPU without BSODs.

Just for this, I even digged in the depths of HP website and forums and finally found BIOS updates (it's a shame system can't fetch you the compatible updates because of Windows 10 is not being supported officialy by HP's older builds.) I updated my BIOS to the latest being 3.08 (2019 release).

First, it was probably a PSU problem. The computer didn't even recognize the GPU etc. Then I got enough power.
Finally after lots of combination and trials/errors, I was able to see the GPU under display adapters section as ASUS R9 200  series. Which is how it supposed to be.

I even uninstalled the integrated graphics card which is Intel HD2500 to avoid any conflicts.
I plugged my monitor into HDMI out and voila! I got "basic" display in 1920x1080 res from just ASUS GPU.

BUT,
The problem starts here, 
Whenever I try to install different versions of the GPU's driver (including which worked with my old mo-bo) it just stucks at around 70% after the monitor is blinked 2-3 times. AND BUMM! "thread stuck in device driver error" and infamous BSOD.
And with that interrupted installation, whenever I restart my computer it just gives the same error and unable to start Windows. The only way out is enabling integrated Graphics and switching back to HD2500 VGA output.

My question is, can somebody enlighten me why does this HP computer resists to this GPU and if there is anything that can be done to resolve this compatability issue, what is it?

Note : Please do not recommend me to change mobo, internal PSU or eventually to buy a small factor GPU w/ 1 fan like GTX 1050ti etc. I'm currently out of money and this GPU is working fine as we have tested it 2 days ago on another computer without problems. I want to take the advantage of this specific GPU on my present system.

Here are my Computer specs ->
HP Compaq Pro 6300 Microtower PC with original mobo.
Intel i5 3470 Processors. 3.20 GHz.
24 GB of DDR3 RAM (8+8+4+4) (Did MemTest, they fully work)
320 W internal original PSU.
Windows 10 64 bit build 1909. 

1 PSU of 300 W + 1 PSU of 500W (These two are external. Each one feeds GPU with 1x 6pin PCIe power cable, both are jump cabled in green and black pins to work parallel with mobo)

GPU Specs.
ASUS R9 285 Strix OC
GDDR5, 2 GB Vid Memory, 256 Bit, 954 MHz GPU clock

Since there is no official support of my computer model in HP website and neither the GPU has official support for such a specific case, I'm desperately seeking help on the web.

THANK YOU SO MUCH!

[wb2001]

@DeepRed,

Put it back to a bootable condition.  Run this program.   What is the BIOS mode?

[DeepRed]

@Wb2001 ,

First of all thank you for your reply.

Actually I've already checked with that and its mode is LEGACY BIOS not UEFI.

But I have some confusion right at this point.

1) Some claim that the relatively old GPU's support both Legacy and UEFI systems, especially Legacy for backwards compatibility. This GPU that I'm referring is a Sep 2nd, 2014 release.
The problem is I couldn't find any exact information whether this GPU is LEGACY BIOS compatible. (Edit : I just want to say that I have used this GPU for the first time with my previous computer that I can't remember if it was UEFI or Legacy(probably legacy) but that one was a 2010 make computer with ASUS p7p55d evo motherboard which worked quite fine with this GPU. This HP 6300 Pro MT is a 2006 make I think??)

2) According to my research, some users of HP are telling that this specific model of HP 6300 Pro MT is UEFI compatible and I see some limited settings in ESC (boot menu) and within BIOS regarding UEFI. I don't know if this is just UEFI emulation.

3) Does switching to UEFI from within Windows 10 solve this problem? If so, there is a method in this link and I haven't tried it yet because I'm not sure if this will cause more trouble or if I can roll back again to Legacy mode in case something goes wrong. https://www.wintips.org/how-to-change-legacy-to-uefi-without-reinstall-windows-10/ 

Thank you very much in advance for your input and efforts!

[DeepRed]

Hi,

Just an update, I don't know if it makes any difference now, but that line reads as UEFI right now.

I did some search on the web and followed instructions from technical forums and converted the BOOT type(?) of the system.

Also chose UEFI Boot order in the BIOS.

And now it's like this.

I don't know if this a valid change but it switched from Legacy to UEFI.
Is this my best bet to try out my GPU in this mode?
I haven't tried to plug it in yet. I'll do so in a few minutes but just wanted to ask if there is anything to be changed additionally  in BIOS.

Thanks!

[wb2001]

@DeepRed,

While you have UEFI, remember that the GPU card only draws 200W.  No need for 2 PSU hooked to the card.

@Paul_Tikkanen,

Do you have any comment? I could sure use your assistance.

[Paul_Tikkanen]

Hi:

Unfortunately, I don't have any suggestions to offer.

The only comment I have is HP business PC's such as the  6300 Pro, which was released to market in 2012, are not designed for gaming, and according to the specs, the graphics card you are trying to install is way too much for that PC to handle.  It requires up to an additional 225W PCIe  6-pin input, beyond the stock power supply.

https://www.asus.com/Graphics-Cards/STRIXR9285DC2OC2GD5/specifications/

Models like the 6300 Pro are designed to use low power graphics cards such as the nVidia GT 1030 and the like.

The PCIe x16 slot is only rated for a max of 75Watts.  See page 11 of the quickspecs link below.

https://images10.newegg.com/UploadFilesForNewegg/itemintelligence/Hewlett-Packard/HP_20Compaq_206005...

You need a high end business workstation to handle a graphics card of that caliber.