Is it a hardware problem?

[Gobbler]

I have this problem on my Windows 7 machine and Vista machine, the problem is that sometimes when I reboot, in case of win 7, the early part of the boot logo becomes invisible and only can be seen in the very later stages of the boot.In Vista, the boot logo sometimes just doesn't appear.Is something wrong with my hardware or is this normal?

[Cudni]

no other visual issues while using the comp?

[Gobbler]

Yes, sometimes my monitor displays no signal momentarily just before the log on screen appears but finally the log on screen does appear.