Radeon 4770 - Underpowered PSU

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
On a similar subject, I've just bought a Radeon HD 4770, which requires a 450W PSU, which I thought I had but turns out that it's only 400w (and not a very good one either).

The computer will POST, make it to the Windows XP screen then cuts out (everything is still powered but won't make it to the Welcome screen) - am I safe to assume that I just require a new 450+W PSU?

 

fpoama

Distinguished
May 17, 2009
60
0
18,630
Might want to post how many amps are on the 12v rail of your PSU. Can you get into safe mode?

What were you using before the 4770? Did you uninstall drivers correctly?
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
I was using a GeForce 8800GT beforehand, which has just recently went pop hence the new purchase.

Haven't a clue how many amps - didn't try getting into safe mode, just took it out in case I was doing any damage and system restored.

I uninstalled all the Nvidia drivers previous to the ATI installation.
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
Truth be told, it won't be the best of PSUs as it came installed in the case which was about 25 quid (I was skint and desperate!).
 

fpoama

Distinguished
May 17, 2009
60
0
18,630
Only reason I suggest going into safe mode was to see if it was a resolution issue with the monitor. So once it gets past the Windows XP loading, the screen goes blank but everything keeps running?
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
Yes, that's it exactly.

Didn't think about the resolution, but didn't really think it to be an issue as I've just been running on the mobo's inbuilt graphics (Geforce 7100).
 

fpoama

Distinguished
May 17, 2009
60
0
18,630
When I switched to Windows 7 it did the same thing. Would show windows loading and then the screen would go blank and it was because of the monitor resolution. Although that was with an on-board graphics. If the PSU was the issue, I would assume that it would shut its self off if it wasn't able to supply enough power.

Hmm your monitor turns off...... o_O
I would just suggest going into safe mode because it will run at a low resolution so you will figure out if that is the problem.
 

fpoama

Distinguished
May 17, 2009
60
0
18,630
Well with Windows 7 I entered into Low resolution mode, which was like 400 x 800 or something, and it worked. So then I gradually increased the resolution, and when I put it at 1028 x 768, I saw that it changed the Refresh rate to 59 Hz when it should have been 60 Hz.
 

fpoama

Distinguished
May 17, 2009
60
0
18,630
Yeah I realize you are running XP, but if you go into safe mode and it works, you might be able to change the resolution/refresh rate.
 
Even though one card might draw more at load then another, the order may be reversed at idle. Can get confusing.

Anyway, you shouldn't power any component you value with a cheap PSU, regardless of whether it apparently works or not. Dying components such as your old card can be caused by a bad PSU.
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
Well I tried all that, and still no luck.

Set resolution to 800x600, restarted in safe mode, worked ok but wouldn't let me change resolution at all and, when restarting in normal mode, still wouldn't get past the Windows screen.
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
Update:

Still no success.

Replaced the PSU as I thought my 400w cheapo pre-installed one could have been the problem. OCZ 600W Stealth (good reviews for the price, mostly a Zalman apparently!) and still exactly the same - gets to the Windows loading screen, then monitor switches off before it gets to the Welcome page.

Tried in another PC and works fine.

The mobo is a Gigabyte GA-73PVM-S2, which switches off the on-board graphics from BIOS, so I can't think that's the problem.

Only odd thing, when I'm running on on-board graphics it can see my Samsung SyncMaster 204BW monitor - when I switch over to the 4770 it only sees Deafult Monitor.

I'm pretty sure the problem is there somewhere along the line, but I've tried reinstalling the monitor driver before installing the GPU drivers and it won't let me - won't recognise the GPU is installed until I put the drivers in and, when I install the drivers, that's when the problems arise.

Ever wish you'd stuck with what you know? (Nvidia never give me these problems :))
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
Well,

I know what it is, pretty much.

Gigabyte sell the GA-73PVM-S2 mobo on the basis that the onboard Nvidia GPU switches off when a GPU is installed.

I don't think it does.

They don't give you the option to switch off manually in BIOS - it's supposed to automatically switch off when a new GPU is installed, yet the IRQs are 'shared' - I'm not a computer genius but at the same time I'm not stupid.

I'll be taking the issue up with Gigabyte; but DON'T buy an ATI card if you have this mobo.
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
UPDATE:

The tech help at Gigabyte has pretty much confirmed that the card is incompatible with the motherboard.

I suggested they could perhaps exchange my mobo for one which works as I can't return it to the dealer due to it not being faulty.

I'm not holding my breath.
 

AMDThunder

Distinguished
Feb 18, 2006
1,239
0
19,310
Disable the onboard graphics in the Device Manager. (In safe mode) I've never heard of a vid card not being compatible with a mobo. Not saying it couldn't happen, but I've certainly never seen it. Well, not counting someone trying to put an AGP card in a PCI-e slot. :)

Also, I'd heard there were issues with the initial release of the drivers for the 4770 that came on the cd. DL the latest ones from ATI.
 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
I've tried that, mate.

In fact, I've tried everything I could possibly imagine.

I've put the latest drivers on, I've updated to the latest BIOS, I've even tried, in case there were some dodgy drivers I couldn't find which could be conflicting, formatted my drive and clean-installed.

I've bought a new PSU and tried another graphics card (which worked with no problem at all), I've also tried my card in another PC (again, no probs).

 

sam_crowuk

Distinguished
Jun 26, 2009
22
0
18,510
To hear a mobo firm grudgingly admit that there could be an incompatibility problem was pretty surprising, I have to say.

Here's what they said:

"I am afraid we can't do more from the motherboard's side.

seems there is some hardware incompatibility between these 2 products"