I would like this thread to be more informative for owners of the M17x with the new ATi cards. I will try to keep this thread as updated as possible. If there is any specific information you want added let me know and I will try to add it.

Bug Found When Over-Clocking the CPU in the M17x with 4870 GPUs

How to Over-Clock Your ATI 4870s
First the disclaimer: I'm not responsible for you bricking your cards. If you are uncomfortable with flashing the BIOS do not bother with this. If you do something wrong and can no longer boot your system I cannot help you and your Dell warranty will be at risk. BE CAREFUL AND EXTRA PARANOID!

Now that part is out of the way there are different ways to over-clock your GPU, here is a quick step by step on how I do it. When doing these steps turn off any CPU over-clocking you may be using.

Tools needed:
A bootable USB stick
ATIFlash
RBE (Raedon BIOS Editor)
GPU-Z

1) Get a copy of your current BIOS and make an additional copy of it and store it somewhere besides your M17x. Do this by placing a copy of atiflash on your boot stick. Turn your M17x on and get into the system BIOS. You need to change the boot order of your system to look at the usb stick first. Then save, exit and boot off the stick. At the command prompt type atiflash -i. When you do this it should report back to you information on your 4870. It will show two cards if you have a crossfire setup. If you notice the cards are EXACTLY the same (I would assume somewhere written in the bios that one card is defined as Master and the other as Slave). Out of paranoia I treat them as two different cards and repeat the steps twice. Now to get a copy of the bios type atiflash -s 0 bios0.rom. This will take a copy of the bios on card 0 and call it bios0.rom. Repeat for the second card, atiflash -s 1 bios1.rom. Like I said before keep an additional copy of the bios files in a separate location. If you want to go back to stock eventually it's best to load the original copies.

2) Use RBE to change the clocks in the bios files. I normally just take my copy of the bios and drag and drop them right on RBE in Windows Explorer. That will open up RBE with the BIOS file loaded. You'll get a warning about the GPU not having ATI overdrive capabilities. Click OK to it. Click on the button on top called Clock Settings. Here is where you'll set your different clocks and voltage to save to the bios file. There is also a little wizard button you can use that will simply ask you how you want the over-clock settings to look like and your under-clock settings. You can use this wizard if you are a beginner. Once you change your clock and/or voltage settings save your bios. In this example I will call it nbios0.rom for card 0 and nbios1.rom for card 1. Put a copy of these two new files on your boot stick.

3) Flash your cards with the new settings. Reboot your system and boot off the usb stick once again. Here is another step to do out of paranoia. Verify that the checksum for your original bios file and new bios file are exactly the same. If they are not it has become corrupted somewhere along the process. Type atiflash -cf bios0.rom (this is the original file) then atiflash -cf nbios0.rom (this is the new file). The output should be exactly the same. Do it also for card 1. Once you are comfortable everything is OK flash the new bios by typing atiflash -p 0 nbios0.rom. It will tell you it's successful (hopefully) and to reboot your system but DO NOT reboot if you have a second card. Repeat the process, atiflash -p 1 nbios1.rom. Once that is successful pull your usb stick out and reboot. Once you're back into Windows use GPU-z to verify your clock settings.

How to Over-Clock your QX9300 to 3.2Ghz
The best thing to do to get the most of your over-clock in your system is to find the best memory divisor. I'm not going to write a long extensive article on how to do this, I will just say most have had good luck with over-clocking by linking the fsb:memory to a 1:2 ratio. This means if you set your fsb to 1280 then set your memory to 1280. If you do research on the subject you'll see the terms double and quad pumped. All this means in the end is to find out how fast the bus is going simply divide the fsb by 4 and the memory by 2. So going back to 1280 the fsb would be 320 and the memory would be 640. Hence the 1:2 ratio. Hope this makes sense.

I bring up 1280 because that is how you would set your fsb and memory to equal 3.20Ghz with the QX9300 if you multiplier was set to 10. 10 x 320 (from the example above) equals 3200Mhz or 3.2Ghz. Easy right? So do it! It will work! Wait it BSOD!! Ok not so fast. I've been having a more difficult time doing this with Windows 7. So here's an old virtual server trick that I tried with Windows 7 and so far it seems to work.

All you're going to do is simply disable the driver for the processor. I've never seen this have a negative impact in the past but then again I don't normally do this on gaming systems. I used to do it to virtual machines all the time when they would randomly BSOD for no reason. OK so here's is how to do it. There are actually multiple ways to do it. If you like doing it from the command prompt knock yourself out. Just like most anything when playing with registry values or Windows services there is a way to execute it from the command prompt. Here is what actually needs to be changed in the registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Processor
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Intelppm
In both these locations there is a "Start" string set to 3. Change it to 4 then reboot. That's it. Next time you go into device manger you'll see the little exclamation on all four cores of your processor. This means you have successfully disabled the processor driver. Obviosly the processor itself is operating at advertised speed. You just don't have a failing driver when over-clocking. So do it again, go into your bios, set the multi to 10 and your fsb and memory to 1280 and boot. Tada! Go ahead and do it again. Set your fsb and memory now to 1300 or 3.25Ghz....TADA!!! Now watch your 3DMark06 score soar since it loves processor speed. Please post your results in this thread!!

Benchmark Highs
3DMark06
Vantage

ATi 4870 Dell Part Numbers
Component Part(s) of X650M
G51FX CRD,GRPHC,HD,4870,XT
C846N SRV,SW,DRVR,VID,AMD,M98XT
H754T ASSY,BRKT,VGA,HTSNK,M17X
Dual – 320-0759, BOMs to MOD D684N, BOMs to
Component Part(s) of D684N
C846N SRV,SW,DRVR,VID,AMD,M98XT
NHCHW CRD,GRPHC,HD,4870,XT,MXM,CBL
G51FX CRD,GRPHC,HD,4870,XT

Coupons
Dell.com/epp has 10% off Alienware systems right now.

Drivers
ATI Mobility Radeon HD 4870 A01 8.635 WHQL driver for Vista & Win7 64b
Version: 8.635-090804a-087472C-Dell, A01
Vista64 | Win7

Pics
Credit goes to SillyHoney@NBR. The pics represent what the red looks like very well.