I've been googling the net all night, and can't seem to find a solution... so I'm hoping someone can lend a helping hand. Here's my problem. I have a K7T266 Pro2 mobo as shown below: http://www.msi.com.tw/program/products/mainboard/mbd/pro_mbd_detail.php?UID=28 Right now, it's powering my AMD 1700+XP cpu. Recently, I purchased a couple 'bundle' computers from a retailer. You know, one of those package deals monitor, keyboard, mouse, everything all together. Anyways, included in the bundle was an AMD 2000+XP cpu. I want to switch the 1700+ out of my 'main' computer, and put in the 2000+ that came with this package deal. I read up on my motherboard, and from what I can tell this motherboard supports up to 2100+XP. Once I switched the CPU's, the computer with the MSI K7T266 Pro2 board no longer boots. When powered on, it will check the floppy, both CDroms and the HD led comes on... but I can't even get into BIOS. In fact, nothing shows up on the monitor. Fearing the worst, I switched them back... but both computer ended up working 100%. This really puzzled me. I found out that there was an update to my BIOS which stated that it would enable support for the 2000+, so I updated my BIOS (everything went well). However, if I plug the 2000+ back in then it doesn't boot up. The FSB on both motherboards (my MSI K7T266 Pro2, and the 'package deal' motherboard read at 133mhz in BIOS. I do not know what the problem is. I have tried everything I can think of. I hope that I'm an ***** and that I missed something really obvious, because that would mean there is a real quick solution. Thanks in advance. [EDIT: -please note the following-] -Both CPU's are Socket A(462) -I've flashed/updated my bios to the latest available -if I take the cpu out, and put the 1700+ in it works fine -FSB is 133mhz in BIOS, same as other 'package deal' machine that runs the 2000+ -both cpu's run fine on their 'own' separate mobo's -I've made sure each time the CPU is placed, that it is seated properly Possible answer? I've checked this page: http://www.msi.com.tw/program/support/cpu_support/cpu/spt_cpu_detail.php?UID=28 It looks like the 2000+XP comes in Palomino (0.18u) 133/266MHz FSB and Thoroughbred (0.13u) 133/266MHz FSB And my motherboard supports Palomino, but NOT Thoroughbred. How do I tell if the chip is Palomino, or Thoroughbred? Other than the fact my PC won't start up, and that could very well be because it is Thoroughbred... is there any physical way to tell? SOLUTION FOUND Found the answer to my problem. Rather than delete this question out... if anyone else can get some use out of this here is the reason for my problem: http://www.pantherproducts.co.uk/Product Reviews/AthlonXP Thoroughbred.shtml The 2000+XP I am trying to use with my MSI K7T266 Pro2 is Thoroughbred, and that is not supported by this mobo. Le crap.