Can you help me please

My N900 is all messed up, i have been having some problems for some months now

Everything started with the usb getting broken, i took it to repair and it got resoldered, as soon as i booted it after that it started with a reboot loop but after some loops it started normaly but from time to time it rebooted and started with the reboot loop again, that happened every couple hours, I asked arround maemo.org and I was told that R&D mode should solve it, it did help but the reboots kept happening once or twice a week.

Last week the usb got broken again and I took it to get fix again, but now that i got it back the reboots are even worst it just stays on for a couple hours and it goes to a reboot loop for a couple minutes before booting.

Any idea on what else can I do? Right now it is on R&D mode and with no-omap-wd and force-power-key flags, it has kernel 51 but is not overclocked, I Flashed this morning and it still doesnt work, please help.

Thank you.