5920G HD4650 problem!

Hi, this is my first post on this site...so please be gentle.
I have an unusual problem with my 5920g. I installed a HD 4650 DDR2 1GB I bought from ebay. Once installed, the computer simply would not show a screen at all. The HD light wouldn't flash after a couple seconds. Nothing appeared to be happening. Have no external monitor with me to test. So I sent the card back for replacement.
The seller contacted me saying that it worked no problems at all in his 5920G.
How could this be? I have installed latest acer bios, and modified bios from the x920g thread. Nothing.

Even more strange was that the card actually worked perfectly on one boot, I installed drivers, rebooted fine, benchmarked the card and everything. Happy as Larry. I then changed the fan settings with Radeon Bios editor, flashed. Everything was well, the program told me it worked and needed to reboot. Back to blank screen, hence sending it back. Only for it to work in another 5920g? Anyone experienced this?

 

You probably got the VBIOS mod wrong, the modded VBIOS is causing a lockup.

You can do a "hot blind flash" by desoldering one pin of the VBIOS chip (make sure that pin is accessible with the cooler installed!), blind-booting the machine from an USB drive with the original VBIOS and flasher tools (to bypass the bad VBIOS that's blocking POST), reconnecting the desoldered pin (e.g. with a screwdriver) and flashing back the original VBIOS.

 

whats the modded bios for? do you need a modded bios to run the 46xx series?

 

The point was that it was like this before I did any modifications. Hence totally confused. Also if the Vbios was wrong, why does that card work in another 5920g. Very strange. Also the modified laptop bios has MXM structure changed, to attempt to allow the 9600m cards. There is no effect of the modified bios to that particular card. Maybe it was just a dirty connection or something strange like that. But odd it didn't work, then worked, and stopped working. Will see what the replacement card is like.

 

The MXM structure change doesn't affect only the 9600M GT, but any "true" MXM card. However, all ATIs I've seen so far had non-MXM VBIOSes.

 

how do you know the seller retested the card, if you think the contacts are dirty rub it down with blank printer paper. as said above maybe you need a vanilla acer bios, as the modded one may be causing problems with the 4650.

 

Well, the seller seemed happy enough to send me out another card. Should hopefully arrive tomorrow. He is also willing to give a refund if this one doesn't work either. So no reason to doubt him.

Dirty contacts was just an idea, I have no other reason to see why it wouldn't work, and did so perfectly for at least a good few hours.

This laptop does have a replacement power adapter if maybe that could be a problem source? Thats a stab in the dark though, and unlikely.

 

That could be it, given that the MXM card receives power directly from the laptop's power jack (and not from a regulated rail).

 

I only suggest that because I have read alot about the power consumption of these machines, and have read that people have bought bigger PSU's to handle the newer graphics cards. Worth a shot buying a better one if this graphics card doesn't work?

Edit* Reading up, the power supply I have here is a 3.42A, genuine acer part is 4.74A if I am correct, going by items available. May order one and its no harm if its not that.

 

I was not thinking about amperage, but line noise/ripple. 3rd party PSUs often use low-quality Chinese capacitors like the infamous Fuhjyyu, which result in excessive ripple in the output voltage.

However, a 3.42A (65W) PSU is definitely not enough - there has to be a reason why Acer only supplies 65W PSUs for notebooks with Intel integrated graphics. Even ones with onboard discrete GPUs get 90W.

Also, my 5720G measures 92W (!) peak and ~85W average power consumption according to Everest with both CPU and GPU under full load. That would destroy a 65W PSU in mere seconds.

 

REALLY! ya don't say. thats a bit of handy info ever since i blew the VRMs on my first desktop boards power and power regulation has been a concern on all my builds and modifications.

thats means as far as high TDP cards you need a decent power adapter and good cooling.

thats another good bit of info having smooth and stable power is a biggie sounds like i'm gonna need to invest in a good power adapter.

 

Yeh I figured it wasn't right for the laptop. However, today I have received and fitted the second 4650, and hey presto worked perfectly. Although, I have to stress that I have changed to a Penryn processor since the 4650 was posted off. Thinking it could still be a power issue. Power adapter certainly feels mighty hot in gaming. But working perfectly.

T8100 idles very cool as well! Room temp 19 degrees, processor reads 23 degrees using Rightmark with slight under volt. Very impressed with that, laptop is noticeably faster as well. Now to wait for SSD prices to drop drastically, or just jump on a 7200rpm drive.

Thanks for all your help!