Computer stuck at boot splash

[TacoBot]

I tried to boot my comp with bare minimum items attached (MoBo, RAM, PSU ONLY) but stuck at boot splash... (supposed to go check CD/DVD at least even w/ no HDD attached) I also don't know what went wrong. It was working, then I opened up and put in a graphics card to see if the gfx is working... next thing I know whole thing won't even boot. I tried with no RAM and it gives POST error code, so the motherboard POST still runs. I also put in a known faulty RAM and it also gave a different POST error code so the POST is definitely working and picking up correct error. But when I insert the RAM that it was working with it just goes to boot screen and stays there. Cannot even attempt to enter BIOS, whole thing just locks up. Tried power cycling and CMOS reset many times also.

MoBo: Asrock B75 pro3-M
RAM: GSkill 1333Mhz 4GB
PSU: Seasonic 620W Bronze

 

[jtjt00]

Try with a single piece of ram. Swap if fail.

 

[TacoBot]

I am trying with a single stick RAM. Don't have any other RAM to try ;_;

 

[TacoBot]

I managed to get another stick of RAM from a friend living nearby, the RAM confirm working one, but when I plug in it give the 4 short beeps then it restarts. Went back to my original RAM, use compressed air to spray the RAM slot, then use eraser rub the contacts, tested on fren's comp working, go back to my comp, not working.

I used the stock thermal paste, but should I check the CPU?

 

[jtjt00]

I am trying with a single stick RAM. Don't have any other RAM to try ;_;

Bring your rig to Nigel at: http://forums.hardwarezone.com.sg/hardware-clinic-2/%5Bsic%5D-new-setup-corner-all-diy-hardwarezoner-%5E-%5E-3581022.html

 

[TacoBot]

I tried inserting the one stick into all the other slots earlier in the afternoon and it didn't work, but I just change the slot and now the computer boots and I don't know why?????

So apparently the first RAM slot isn't working, but the other slots are. Wonder if I should RMA especially cos it's such an old board + I don't have the receipt so cannot even guarantee if can RMA. What should I do? :x