4850 BIOS Flash Sets Idle Clock Right

So I bit the bullet and tried the updated BIOS for my 4850. After setting my card back to defaults in the CCC, it started to idle properly.



Instead of idling at 500MHz Core and 750MHz Memory, it's now idling at 160MHz Core and 500MHz Memory.

I'm going to run some benchmarks to see if there's any performance loss from this BIOS.
Okay, I've ran a few benchmarks and it performs identically and feels identical in gameplay too.

Which manufacturer, and which BIOS?

My card is an HIS model but the BIOS I used is the MSI one.

I did a MD5sum on the original BIOS from HIS and MSI and they were absolutely identical (as are every single other 4850 except the Asus one). I reasoned that the BIOS should thus work without any issue and it did.

Do you know the MSI bios supports fan control?

I think Asus's tool simply detects their own cards which means a tool that can control the fan for all models should be possible regardless of the BIOS.

Originally Posted by ChronoReverse

My card is an HIS model but the BIOS I used is the MSI one.

I did a MD5sum on the original BIOS from HIS and MSI and they were absolutely identical (as are every single other 4850 except the Asus one). I reasoned that the BIOS should thus work without any issue and it did.

My Asus 4850 is on the way. Does the Asus card idle properly?

Any results yet on your benchmarks?

I've updated my original post and it performs identically.

The Asus cards are like all the other cards and idle at the incorrect clocks. This BIOS came from the newer MSI cards apparently.

So all the 4850 and 4870s in the wild will need a bios flash? Wonder how many will die in the process. RMAs galore. Lame.

I don't know about that. It's clear that the chips can survive at that temperature because load isn't much higher.

If the cards can't survive long periods of load on stock, then they'd be pretty useless.

The only real effect of this BIOS is cooler idle temperatures and lower overall power draw.



Incidentally, it'd be nice if someone with the stock cooler tried this. I have a 3rd-part cooler so the benefits of this BIOS is marginal at best. I wonder if the idle temperature would drop significantly.

Originally Posted by ChronoReverse

I've updated my original post and it performs identically.

The Asus cards are like all the other cards and idle at the incorrect clocks. This BIOS came from the newer MSI cards apparently.

Do you know if MSI bios will work on Asus card?

Thanks!

Keep us informed, this is interesting.

I've also got an Asus 4850 on the way. Will it be possible or necessary to flash the BIOS to address the fan speed issue? I'd like this to work nice and cool, not like a space heater

The ASUS supports fan speed control.

I've corresponded with Forge a bit at the Techreport forums and he sees a drop from 80 Celsius idle to 65 Celsius.

Not a tremendous drop but still brings it down to a lot more comfortable levels. He set his clocks using a BIOS editor though so perhaps the MSI BIOS has even more tricks to bring the temperatures down. It would be great if someone tests this on a stock 4850


With BIOS edits you can also change the rates at which the auto-fan speeds are set but it doesn't appear to be necessary if you simply have this BIOS as the temperatures are already quite manageable.


http://www.techpowerup.com/vgabios/i...ace=&memSize=0
Use the MSI June 5, 2008 BIOS

What tool do you use to flash the 4850 bios?

ATIFlash
http://www.techpowerup.com/downloads...lash_3.59.html
Which must be run from DOS.

If you have only one card the command is:
atiflash -p 0 <bios.bin>

WARNING DO THE FLASH AT YOUR OWN RISK. IF YOU DAMAGE YOUR CARD IT'S NONE OF MY FAULT.

You can also use ATIWinflash.

With that said, just tried it on my VisionTek 4850 but it still idles at 500/750. Only saw it go to 160/500 once - for a fraction of a second. Back to the original BIOS for me, it seems.

Did you remember to hit "Defaults" in the CCC and then apply after hitting "Test Custom Clocks"?

Originally Posted by ChronoReverse

Did you remember to hit "Defaults" in the CCC and then apply after hitting "Test Custom Clocks"?

No, silly me. Works now.

What kind of idle temps are you getting though? I'm curious if it reduces it for you.