Hi i have problem with memory stick , every memory i used with frequency of 400 mhz i got " no signal" screen after i shut down and power up the computer. i tried some no brand comemory stivk - 128 ddram with 266 mhz speed and it works fine . when i replace back to the kingston KVR 400 pc 3200 400 mhz OR to HYNIX PC 3200U serial number - HYMD232646B8R and shut down the computer then power up i get "no signal" . please tell me what can i do , i replace already 3 sticks of memoy and the motherboard. Regards DRU.