So I have a Dell Optiplex 790 MiniTower that I got used a couple years ago from a buddy whose company was replacing their servers. When I got it it had a 128GB SSD, 16gb(4x4gb) ddr3 RAM, an Intel i7 3.4ghz with on-board graphics and a 240w power supply. Everything was going great for a while and I even installed a secondary 1tb SATA HDD and was dual-booting windows 7 x64 and xubuntu with no problems, but then when I tried to install a new GPU everything got screwed up.
Now I apologize if I'm missing any key information here because it was a long time ago and I've tried a lot of things with this machine at this point...
Basically I was dumb and forgot to check the PSU requirements before getting a gigabyte gtx 750 ti, which I later realized required too much power for my wimpy 240w stock power supply. I also found out later about the 35w limit on the 12v rail in this Dell model which limits GPU options. I tried borrowing an old 450w thermaltake that my friend wasn't using anymore but when I installed that and tried turning the machine on it didn't work (I can't remember anymore if it was just unresponsive or if it flashed diagnostic lights, but it didn't go farther than that.) Looking back I realize I probably had something plugged in wrong and should have read the manual better or something, but instead I tried plugging the wires in differently, an even tried flipping the voltage switch on the back of the power supply at one point.
When none of that worked (Sorry I can't be more specific right now about error codes and such), I tried putting the hardware back the way it was when I got it, but then I got error codes referring to a GPU failure and still wouldn't boot. When I called dell they said that if I was getting that code without a gpu installed then it meant there was something wrong with the on-board cpu graphics and therefore the motherboard, but that I could try resetting the bios or putting in another GPU.
Next I got a decent 600w power supply and made sure it had safe-guards against frying the motherboard and that kind of thing and it actually booted! Unfortunately the VGA port doesn't work anymore, and about 5 minutes after booting I got the blue screen of death(windows) or a kernel panic(linux). It can last about 15-20 minutes running a recovery CD (Hiren's boot cd) but when I try to boot the same program through USB I get the BSOD as soon as it loads into mini-xp. It is able to stay alive significantly longer for chkdsk, perhaps about 40 minutes, so I was able to test everything individually through that and it seemed fine except that the computer can only see 2 of the 4 memory sticks at a time(I checked them all individually and chkdsk said they were okay.
In addition to all that, the ethernet adaptor also seems to be malfunctioning. It recognizes when I plug the cable in but keeps saying it's unable to assign a dhcp address or something. Pinging the local router seems to work but google does not.
I tried hard-resetting the bios by taking out the coin battery, but that didn't seem to do anything. I may not have left it out long enough.
So finally my question to you all is this: Am I overthinking this way too much by looking for a non-motherboard problem, or is it still worth it to try to rule out driver-related issues before spending the money and risking messing up the hardware any more by changing out the motherboard? Also, if I need a new motherboard would the same one that came with the dell be sufficient (with the 35w limit on the 12v rail) since I have the power supply to handle it now anyway, or will I need to get something else?
Now I apologize if I'm missing any key information here because it was a long time ago and I've tried a lot of things with this machine at this point...
Basically I was dumb and forgot to check the PSU requirements before getting a gigabyte gtx 750 ti, which I later realized required too much power for my wimpy 240w stock power supply. I also found out later about the 35w limit on the 12v rail in this Dell model which limits GPU options. I tried borrowing an old 450w thermaltake that my friend wasn't using anymore but when I installed that and tried turning the machine on it didn't work (I can't remember anymore if it was just unresponsive or if it flashed diagnostic lights, but it didn't go farther than that.) Looking back I realize I probably had something plugged in wrong and should have read the manual better or something, but instead I tried plugging the wires in differently, an even tried flipping the voltage switch on the back of the power supply at one point.
When none of that worked (Sorry I can't be more specific right now about error codes and such), I tried putting the hardware back the way it was when I got it, but then I got error codes referring to a GPU failure and still wouldn't boot. When I called dell they said that if I was getting that code without a gpu installed then it meant there was something wrong with the on-board cpu graphics and therefore the motherboard, but that I could try resetting the bios or putting in another GPU.
Next I got a decent 600w power supply and made sure it had safe-guards against frying the motherboard and that kind of thing and it actually booted! Unfortunately the VGA port doesn't work anymore, and about 5 minutes after booting I got the blue screen of death(windows) or a kernel panic(linux). It can last about 15-20 minutes running a recovery CD (Hiren's boot cd) but when I try to boot the same program through USB I get the BSOD as soon as it loads into mini-xp. It is able to stay alive significantly longer for chkdsk, perhaps about 40 minutes, so I was able to test everything individually through that and it seemed fine except that the computer can only see 2 of the 4 memory sticks at a time(I checked them all individually and chkdsk said they were okay.
In addition to all that, the ethernet adaptor also seems to be malfunctioning. It recognizes when I plug the cable in but keeps saying it's unable to assign a dhcp address or something. Pinging the local router seems to work but google does not.
I tried hard-resetting the bios by taking out the coin battery, but that didn't seem to do anything. I may not have left it out long enough.
So finally my question to you all is this: Am I overthinking this way too much by looking for a non-motherboard problem, or is it still worth it to try to rule out driver-related issues before spending the money and risking messing up the hardware any more by changing out the motherboard? Also, if I need a new motherboard would the same one that came with the dell be sufficient (with the 35w limit on the 12v rail) since I have the power supply to handle it now anyway, or will I need to get something else?
Facebook
Twitter
Instagram