In another what I assume is a soon-to-be-deleted superuser question, due to the affectations of the moderator squad there, a user asked:
"I have a socket 1155 motherboard (P67 chipset with i5-2400) that died. What do I need to consider for a replacement?"
Here's my answer (extended a little here to try and cover all bases), in case it helps anyone else going through the same process:
The i5-2400 will work with pretty much any socket 1155 motherboard, so you can look at the boards that were released with SandyBridge CPUs — for example, H61, H67, Z68 — as well as those that were released for IvyBridge CPUs, such as B75, H77, Z77.
Most board manufacturers have a CPU compatibility list for each board, so if you find a particular board, you should be able to confirm by searching for the make/model.
Given that they're not made any more, finding a "good" replacement might be tricky. As long as the motherboard has all the ports and sockets you need, it should do the job. In the general case, some of the factors that should be considered:
- What sized case do you have? Physical size is imperative: An ATX motherboard won't fit in a micro-ATX sized case, for example. A board that is otherwise suitable must fit the case, otherwise it is pointless to consider it.
- Number of and/or combination of PCI and PCIe slots required. All current motherboards have at least one PCIe x16 slot for a graphics card, and keep in mind that most graphics card take up at least two slots.
- Number of RAM slots required. Some low-end boards only have 2 RAM slots — if you have more sticks than that it might mean you either have to reduce your amount of RAM, or buy a new kit with larger size per stick.
- Number of SATA ports. Most drives (hard drives, DVDs, and SSDs) around in the socket 1155 timeframe used SATA as the connector type. Make sure the motherboard has enough SATA ports for all your drives.
- Number of USB ports required. In addition the ports on the motherboard, consider what USB ports your case has. Any USB 3 ports will most likely require a USB 3 header on the motherboard, which are physically different sizes to USB 2 headers.
- Number and type of onboard graphics ports. If not using a dedicated GPU, consider what types of onboard graphics connectors you need.
- Number of fan headers. Required for case fans
- Chipset matching to avoid confusing your operating system. You may want to attempt to match the existing board — by chipset and/or manufacturer — in order to reduce the risk of your operating system from "rejecting" the change.
- Overclocking support. If overclocking with a 'K' CPU, choose a 'Z' chipset
Most DDR3 RAM will work with any board, but you can also try and confirm RAM compatibility either with the motherboard or RAM manufacturer's compatibility lists.
The i5-2400 which has limited overclocking potential is a little easier to source a replacement that for an overclockable 'K' CPU. In the latter case, the Z68 or Z77 boards are the best choice as they support overclocking.
2nd hand is most likely a cost-effective option if you can find one. Some socket 1155 boards are still available at online stores, so you could check Newegg, Amazon, and similar places. Alternatively, you could call a few local computers stores to see if by chance they've got old stock.
As an example of the process: here's a listing for the Gigabyte B75M-D3H at Amazon. The CPU support list shows that the i5-2400 is supported. It has 4 RAM slots, and after the GPU is in will have a PCI and PCIe slot free. It is only micro-ATX sized, so should fit all but the smallest cases.
When replacing, if you change the make and model of the board, you may have difficulty booting your OS with the updated board. This depends what OS you're using, and how different the replacement board is as far as drivers go. Windows traditionally hates hardware being replaced, and may refuse to boot; if you were using, say, Linux it would most likely just work. So keep that in mind that some recovery — or worst-case, a reinstall — of the OS might be required. Finding an exact model motherboard should avoid this issue; finding a similar chipset should reduce the risk of boot issues (but licensing issues may still need to be dealt with).
During the replacement process, after removing the heatsink, clean existing thermal paste from the CPU and heatsink using isopropyl alcohol. Reapply fresh paste before putting the cooler back on the CPU when it's installed in the new motherboard.
(As an aside, confirming that a motherboard fault is the problem — and not something else like a dead power supply — is a worthwhile activity to go through first).