Asus P8Z77-V CPU LED and RAM red flashes - won't boot

[vmars4eva]

Hi, this is my second time building a PC. When I went to boot my new PC for the first time, the red CPU LED flashes briefly, then turns off, then the DRAM LED flashes briefly, and then turns off. The MoBO main LED remains green throughout all this.

Here's the build:

CPU - i7-3770K LGA 1155
MoBo - Asus P8Z77-V
PSU - Antec High-current Pro HCP-850 TX12V v2.3
Case - Corsair Carbide Series 400R
Cooler - Cooler Master Hyper 212 EVO
SSD - Samsung 840 Series MZ
RAM - G.SKILL 4GB 204-Pin DDR3 SO-DIMM DDR3 1600

I checked this forum and read that the red CPU LED points to something wrong with the CPU and to check for any bent pins. This first time this happened, I could not find anything wrong with the CPU socket. I tried with one stick of RAM in each slot, and no luck there. I got a PSU tester and everything checks out fine, but the -5V LED on the tester does not come on when I check the 20+4 connector (and when I looked at the connector, I found a hole, but read online that this is OK). However, I had gotten thermal paste all around the socket area from putting on too much thermal paste when I installed my Hyper 212 EVO, so I figured that I had damaged the CPU and the MoBo with thermal paste during this process (or something else was wrong). I cleared out the thermal paste with rubbing alcohol (91%) and tried again, but same LED red flashing.

I exchanged the CPU and the MoBo, and am now on my second of each. However, the same exact thing happens (and I was much more careful with the thermal paste this time). Now, if it's not the CPU or MoBo, what could be the culprit? I did find out online that I was installing the standoff nuts incorrectly (as in installing them at all, I did not realize it was OK to just use the preinstalled standoffs) so I am going to try reinstalling the MoBo today without the standoff nuts.

Any tips on what could be going on would be much appreciated. I tried to find online if there are any compatibility problems with this combination of parts, and I notably could not find Antec Pro 850 paired with the Asus P8Z77-V anywhere. Wondering now if that is the problem.

 

[alexoiu]

Hi, The CPU and RAM leds are supposed to flash when starting the board as the system tests the components. If one of them remains lit then it signals an issue with that component. Since they go off, then it's OK. How do you connect the monitor (DVI or HDMI)?
If HDMI, try the DVI or VGA.
When installing the board inside the case, use the standoffs. Make sure they match the board's holes (an extra standoff would short the board).

 

[vmars4eva]

Hi, The CPU and RAM leds are supposed to flash when starting the board as the system tests the components. If one of them remains lit then it signals an issue with that component. Since they go off, then it's OK. How do you connect the monitor (DVI or HDMI)?
If HDMI, try the DVI or VGA.
When installing the board inside the case, use the standoffs. Make sure they match the board's holes (an extra standoff would short the board).

Well, I believe the case has preinstalled standoffs, though it did come with three standoff "nuts". I think they're for if I am installing a different type of MoBo. There are preinstalled standoffs for each of the nine holes the MoBo needs. There are only eight screws, though, so I wonder if it's OK if one does not have a screw.

 

[alexoiu]

It's OK with 8 screws. Before installing it in the case, I would start it firstly, just to make sure it does work. Put it on its box, install only the necessary components (one RAM stick, DVD drive, keyboard and mouse) and see if it does POST.

 

[vmars4eva]

It's OK with 8 screws. Before installing it in the case, I would start it firstly, just to make sure it does work. Put it on its box, install only the necessary components (one RAM stick, DVD drive, keyboard and mouse) and see if it does POST.

Wow, what a relief! That did work... Sort of. Instead of flashing the CPU LED and then the DRAM LED and then shutting down entirely, I got it to flash the CPU LED, and then the DRAM LED, but then it stayed on the DRAM LED instead of just shutting down entirely. That's definitely progress. I then unplugged everything and placed the MoBO in the case again on the preenstalled standoffs, and it is working there too now.

But, I apparently now have a RAM problem to deal with... It does not like the 1600 G.Skills I have. I took a RAM stick from my old computer, a 1333 Hz, and placed it in the second slot, and it finally booted up. Either I need to get a new set of RAM, or I damaged the MoBo somehow at the RAM ports, because though it likes one stick, it will not work with two sticks. Just one. Also, the top two USB 3.0 ports will oddly only work in the BIOS screen, and not when I got to install Windows... I hope there's no damage. Thanks for your help, Alexoiu!

 

[alexoiu]

If a RAM slot does not work (assuming that the RAM module is properly inserted), it might be a CPU socket bent pins issue.
When installing Windows, use the USB 2.0 ports. There's no damage, USB 3.0 drivers are required.