This is basically the information I have on the SLI problem so far.
First of all, my system specs:
Alienware Area-51 M9750
Motherboard - Arima W835DI (AMI BIOS)
CPU - Intel Core 2 Duo T7600 @2.33Ghz 667Mhz FSB 4mb Cache
HD - Hitachi SATA 200GB 7200 RPM x2 (Raid 0)
Video Cards - Nvidia GeForce Go 7950 GTX 512MB x2 (SLI)
RAM - 2GB Y9530 QIMONDA PC2-5300 DDR2 @667 Mhz
OS - Microsoft Windows XP Professional x32 bit
Second of all, my warranty is no longer in effect so that is why I'm posting on here for help with this SLI problem. So anyway, I woke up one morning (left my laptop on overnight) and my PC had a BSOD. After being puzzled by it for a minute, I decided to just shut off my PC and restart it. My PC kept getting a blue screen and rebooting right after the Windows splash screen right before the user login screen. Unable to read the output for the BSOD because auto reboot was enabled, I reinstalled Windows thinking something might have happened to Windows. After reinstalling Windows and all of my drivers my computer worked great. Then I finally got to the point where I enabled SLI, and my computer crashed and started another BSOD loop of BSOD -> reboot, etc. After a few times of this happening I finally got something from the BSOD which was "nv4_disp.dll". Figuring nv4_disp.dll had something to do with Nvidia, I decided to reboot in safe mode and uninstall my graphics driver. Problem solved, I was able to boot in to Windows normally now. So that's when I finally figured out my BSOD problem had something to do with my video cards. I searched for the most up to date video driver and installed it, then enabled SLI and again BSOD. nv4_disp.dll always kept coming up as part of the BSOD. So I did some research and just about every solution for it was to reinstall the graphics driver because apparently the issue was nv4_disp.dll going in to an infinite loop and crashing Windows.
Well, I reinstalled the driver again several times, even using the original driver I got with my Alienware straight out of the factory that I knew SLI worked with before, up to the latest driver (I can't remember the version I used at the time, but it was like... 140.something?). Anyway, I just finally said forget it and used the PC in single card rending and gave up on SLI for a while. A few months later, it was suggested by a buddy of mine that one of my video cards or the SLI cable was probably dead because I showed him the SLI problem, which is basically every time I enable SLI my computer BSOD and I have to reboot in to Safe Mode and uninstall the graphics driver. He suggested I take both of my video cards out (the Parent and the Daughter) and install one at a time in the primary slot to figure out which card was dead. Well the Daughter card worked in the primary slot (being the primary card of course) and the Parent card did NOT work, which lead me to believe that was the card that was fried. So I ended up calling Alienware for a new set of cards, and of course they do not have any because the computer is over a year old, which I thought was dumb. Anyway, I finally got a new set of cards on E-bay with a new SLI cable.
So I installed the new set of cards and then tried enabling SLI again. Now this time when I enabled SLI, the screen just went black. No BSOD, just a black screen. The backlight of the monitor kept turning on and off, but nothing would show up on screen whatsoever. Then I turned my PC off and tried installing the new SLI cable I got. Same thing. So I decided to take both cards out, and like I did before, test one at a time in the primary slot and booting up the PC to see if they both worked. Again, the Parent card did not work. So I'm wondering how did I get TWO bad Parent cards? One was brand new! I called up Alienware tech support and talked to them for a few hours several times throughout several days and got a few suggestions:
1. Update/reinstall my video driver - did it SEVERAL times before the call and again over the phone just to humor him
2. Reinstall Windows - already did but would not do over the phone because it takes a bit to do
3. Try a new set of video cards - already did, and tried a combination of both sets as well
4. Remove the CMOS battery from the motherboard and restart PC
5. Remove the SLI cable and enable SLI to try to "force" the PC in to SLI mode
6. Update my BIOS (which was what my first post was about, it went horribly wrong but I fixed the issue)
Now the agent said if any of that didn't work, one of several things could be the problem:
1. One of my video cards is bad. Well no kidding, but I got a new set and neither worked in SLI. Also, apparently the Parent and Daughter card have different BIOS on each card, so my method of figuring out which card was bad (i.e. one card at a time in the primary slot) didn't work because of that. No matter what, the Parent card won't work in the primary slot so the agent said the only way to know if that card actually works is to enable SLI... which I can't.
2. The SLI cable could be bad. Same as cards, I got a new one.
3. Heat could be an issue with either the cards or the north bridge. However, I've tried to enable SLI right after boot when the computer hasn't been used so it didn't even have time to overheat. I don't think that's the issue.
4. The SLI selector card could be bad. Yeah, but actually my laptop doesn't have one so this is impossible.
5. One of the video card slots on the mother board could be bad.
6. Some circuit that regulates the power on the mother board can be blown which apparently only affects my SLI
So after the call, I tried suggestions 4, 5, and 6 (removing battery, SLI cable, update BIOS) and none of them worked. With the new cards, I just kept getting that black screen that would never changed, and the backlight turning on and off. With the old cards, I kept getting the BSOD that always said nv4_disp.dll. I installed the latest driver from Alienware's website which was 169.something and that did not work either. So after some more digging around on the net, I found
http://forums.laptopvideo2go.com/topic/160...rkaround-xpx32/ . Apparently this system has problems some times running SLI because several people have had it, so this guy posted a "workaround" for it. I followed the advice in the first post which basically suggests:
1. Uninstall your driver
2. Get the most up to date forceware driver from laptopvideo2go.com (driver v195.39) along with the new .inf file that comes with it.
3. Install the driver for your first card, but cancel the installation for the second.
4. Reboot
5. "update" the driver for your second card in the device manager, pointing to the folder of the new driver downloaded from laptopvideo2go.com (driver v195.39)
6. Reboot
7. win
Ok, so I got through steps 1-6. At this time, I had my old factory default video cards installed. I went to enable SLI in hopes of achieving step #7, but it appears that I never actually won. For the first time, I finally saw my desktop (or at least most of it) after enabling SLI. It looked like SLI was finally going to work, then after a few seconds I got a BSOD so I was wildly disappointed. My computer would reboot, get to the user login screen of windows and render part of it out on the screen, then BSOD and reboot and keep going in a cycle. This time, the BSOD referenced nv4_disp, not nv4_disp.dll. I uninstalled the driver and took my PC apart. I cleaned all connectors with denatured alcohol and put new thermal grease on it (I used OCZ Freeze which when I did research, is supposed to be one of the best out there). I forgot to put new grease on it after taking it apart the first time so it had the old grease on it. So I knew I was having a bit of a heat issue so I figured I'd seal everything up properly. Anyway, after getting it all put back together, I turn my PC on and log in to Windows, enable SLI, and this time immediate BSOD. It didn't even switch over to SLI and start rendering out my desktop before the BSOD, just immediate crash. I got the stop error code this time which read:
PAGE_FAULT_IN_NONPAGED_AREA
0x00000050 (0xD22A81BC, 0x00000000, 0x8052AB60, 0x00000000)
nv4_disp.dll is no longer in the stop error now though in any shape or form whatsoever. I did some research for that stop error online and came up with a few reasons for it. One was due to a video card problem. Another was a video driver. My cards both appeared to work, and I've reinstalled this driver about a hundred times already. The current driver I'm using is the forceware v195.39 from
NVIDIA & Laptop News | Latest NVIDIA drivers and related news | laptopvideo2go.com. Currently, I have no idea if for some reason, after all the drivers I've tried, there is some problem with them that they cannot enable SLI properly. I'm unsure if it's the Parent video card that's the problem. I put new thermal grease on my PC on all of the good parts and stress tested it and benchmarked, and the heat dissipation is working very well now so that's not an issue. I mean the PC works ok in it's current state only using one card, it's just that every time I enable SLI it crashes and I have no idea why. I just don't know what else to do or where else to go from here. Just about everything I've tried has failed. If anyone has any idea why I cannot get SLI to work or some other ways to troubleshoot this problem that would be a Godsend. I've worked on this way too long and did way too many things and I'm past the point of frustration right now. Any and all help would be appreciated.
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