Oh crap, I hastely bought a new processor for my aging PC off newegg, and now I am worried that it may not be compatible. My MB is an INTEL DP965LT.

I bought this processor

Intel Pentium E5300 Wolfdale 2.6GHz 2MB L2 Cache LGA 775 65W Dual-Core Desktop Processor

http://www.newegg.com/Product/Product.aspx?Item=N82E16819116074

My board supports Dual core 775 socket type and 800 mhz FBS. However, when I looked on Intel's compatibility page, I didn't see anything for E5300.

Should I be worried? More on my MB:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813121035

should be fine i put a 6750 on my old abit mobo that wernt on there list and that worked fine

It will work, and it's a great upgrade even if it's far out-dated. I run the E8400 at 3Ghz and watch the benchmarks very closely and I'm nowhere near impressed enough with the newer chips to trade up yet. It's a good chip!

Yes you are in the clear, on a sidenote I kind of remember someone on this board mentioning older 775 boards cant take q9xx not sure, not that it mattered anyways.

Thats a really old s775 motherboard! (P965 chipset)

Im almost ceartian that you would have to change the bios to a late version to make use of the 45nm C2D CPU's. (E5x00, it's C2D but with less L2)

But to make sure, if you ordered a new motherboard the bios could be already up to date, if you already got the motherboard and had it since it was new you would need to update the bios.