Pros: Features.

Cons: Controllers burn out. Had this happen on two boards now. First board died after I attempted to use the eSata port. This second board lasted 3 months, and just died all on its own. Windows 7 giving me random freezes despite 2nd new install. Able to be used, but I keep getting several drive controller errors for more than just my main HDD. The HDD tests OK... gotta be the board.

Pros: Works great and the utilities that come with it work good as well, although I don't really utilize them (yet). I like that it has legacy capabilities like IDE and PCI since I reused an IDE/ATA DVD burner, though some might not find this as a pro necessarily. It is a great buy for budget builders.

Cons: You can damage the board if you use the powered eSATA ports on the back if you have a SATA (such as a HDD) device plugged into SATA ports 0 or 1 (or is it 1 or 2?). Therefore plug your HDD and optical drive into SATA ports 3 and 4 if you plan on using powered external devices. Also, the audio lead/pin is in a very stupid place right above where you'd put a graphics card, although this won't affect everyone and really isn't THAT bad.

Other Thoughts: System Specs:

i5-750
ASROCK P55M Pro mobo
4g G.SKILL Ripjaw RAM
HIS ATI 5570

Everything works great so far!

Pros: Solid motherboard for enthusiasts on a budget. Phenomenal value, very satisfied with this board.

Cons: ASRock's instant boot isn't really as great as it sounds. All it really does is just reboot your computer (it MUST reboot) and then immediately puts your PC into sleep mode when it gets to your desktop for a 'clean boot.' Kind of a gimmick, but whatever.

Other Thoughts: Intel Core i7 860 @ 3.4Ghz w/ Arctic Silver 5, ASRock P55M Mobo, Arctic Cooling Freezer 7 Pro Rev. 2 AM cooler, 2GB DDR3-1600 Crucial Ballistix Tracer w/ Blue LEDs, 600W PSU w/ dual LED-backlit fans, 500GB WD Blue HD @ 7200RPM, Radeon X1300 (will upgrade video card soon)

Pros: -Price
-Socket 775 heatsink compatibility*
-Clear area for a large heatsink (fits Xigmatek HDT-S1283) and still use x16 PCI Express Slot
-USB Bios Flash
-Wake on Lan

Cons: -Only recognized 4 of 8GB one time - reseating RAM solved this and RAM had just previously been removed, though BIOS recognized all 4 2GB sticks despite showing 4088MB RAM?!
-Included software typically cheesy ui, though somewhat useful (IES)
-Wake on Lan requires several non-intuitive BIOS changes including enabling PCI Wake in Advanced -->ACPI
-Only 2 SATA Cables included
-Annoying, though still usable audio header location
-Foxconn connector - as others have noted

Other Thoughts: *Has pins for Socket 775, but be aware that the Socket 1156 CPU has a metal support bracket on the backside - unlike Socket 775. I purchased the Xigmatek ACK-I7361 adapter (775&1366 compatible) and had to perform a little bit of a hack to get the back support to rest properly - take a look at the install manuals of the ACK-I7361 and ACK-I5361 to see why and notice the convoluted shape of the ACK-I5361 - its to avoid hitting the bolts from the socket.

Speedfan doesn't detect temperatures properly (can be up to 20 C off) for this Mobo - use HW Monitor, Core Temp or Real Temp.

I've had no issues with the USB ports - front ports can power a 2.5" USB HD

For general compatibility info:
-Core i5-750
-Asrock P55M Pro
-8GB Kingston KVR1333D3/2GR - not on Asrock QVL, but same Elpida chips as others on the QVL (A-Data notably)
Asus Nvidia GSO 9600 512MB GDDR3
-Xigmatek HDT-S1283 Cooler w/ ACK-I7361 mount - buy the ACK-I5361 if possible.
-2 WD 7200rpm HDs (no raid)
-Corsair CX400W

Pros: Features for the money. Bios updates seem to work well. Bios was easily flashed to 1.70, although CMOS cried ERROR until next reboot. Was just fine after that.

2nd board is doing well after 4 days. I'm going to avoid ever using the eSATA (see cons).

Cons: My first board fried after I plugged an external drive into a backside eSATA port. Disgustingly, the manual has buried the warning that if you plug something into the external eSATA port/s while an internal SATA HDD is plugged into internal port 0 or 1, you may damage something. I did -- it killed my board's HDD controller, which made the board unable to boot. Had to return the mainboard for a replacement. I wasn't a happy camper! I felt like I had to go on an Easter-egg hunt to find this warning.

Asrock replies to e-mails about support, but takes 3 days. No phone support.

Also, USB ports don't provide enough power to run my 320gb notebook HDD. Asrock said: Please set the PS2_USB_PW1 jumper to +5v (1-2) and try again. It was already set this way, yet still didn't work. Back ones will work sometimes, but not always. Tried different cables, and one will work (but all cables work on 3 other computers). This has been an issue with both p55m pro boards I've owned.

Other Thoughts: This Asrock board eats 10w more power in idle mode (6 watts more than others if you use the IES power saving utility). IES will save you 20 more watts over competitors under load, though.

Pros: Its solid, and the BIOS-based flash update made me happy. Also, its cheap.

Cons: It did not in fact "get in the kitchen and bake me a pie."
Probably does not overclock well, but that's not a concern of mine.

Other Thoughts: The makes ASRock board #4 for me, and I've yet to have a major issue.

Pros: I was waiting to build a Lynnfield system for quite some time. Finally had the opportunity and picked this board. After a few initial kinks it turned out to be a very good board.

All components run cool and rarely overheat (which is surprising since my system is built in a CM 360 Elite). Installed it with an i7 860 and 4 GB of DDR3-1333 with Win 7 Ultimate. Runs like a dream......

Finally a company with the stones to put Socket 775 holes. Which means your selection for 3rd Party HSF just about tripled!!

I have yet to have any BIOS issues with it whatsoever.
I won't comment on Fan Header Placement since I use a Fan Controller.

Overall an excellent board!

Cons: Memory Installation was a bit on the fussy side. I loaded power to the computer but for the first time it wasn't booting rather, it was going thru a loop of powering on and shutting down.

This told me that the motherboard is working properly and I had to either reseat the CPU or the Memory. I did the easier of the two and reseated the memory and lo and behold it posted!

Although this was an error due to my own fault so I don't if this can be a con. Just take great care installing components.

Other Thoughts: Glazed Donuts are wonderful!!

Pros: Lots of features.

Cons: USB front headers don't provide enough power for external drives (even when using 2 plugs). I read online that it's a problem with more than just this Asrock board. Apparently, it's a P55 chipset issue other users of p55 boards from other manufacturers are encountering. I can only hope it will be addressed in firmware updates somehow.

Other Thoughts: Really disappointed in the USB front header issue.

Pros: Lots of value for the money.

Cons: None at the moment.

Other Thoughts: I am just updating my earlier review where I said there was a whine from my board's audio. For whatever reason I can't explain, when I installed Windows 7 (formatted over XP) the whine went away. I wonder if it had something to do with the audio driver? Or perhaps the XP settings turned something on in audio that Win7 turns off/down? I have no idea. Anyway, the whine is gone!

Pros: Lots of nice features for a cheaper board.

Cons: Ultra high-pitched whine coming from the sound output. :( It happens to whatever I plug into the green sound output port. Even headphones do this. Very frustrating.