1) You need to know what processor socket is on the motherboard.2) You need to know what the Northbridge chip of the motherboard chipset, is.3) There may be a BIOS upgrade needed, in order to support the processor upgrade.OR, alternatively there may be a CPU (Processor) Support list.Let's go to HP Support, and find out,
http://www8.hp.com/us/en/support-drivers.htmlLeft-click on the purple middle 'box', with Product Support and Troubleshooting in it.In the box that is under the heading - Enter a product name/number, left-click in the box.Type Pavilion a620n. (Pavilion is an HP line. HP Support doesn't need HP put in the box)Now go to the right of the box, and left-click on Search.Give it a second, and the main support page will come up, for the Pavilion a620n Desktop PC.Left-click on Product Information. Left-click on Product specifications in blue.In the list left-click on -Motherboard Specifications - A7V8X-LA (Kelut)If you scroll down there is an illustration, and photo of the Pavilion a620n's motherboard.Note in the Illustration that the processor socket is a Socket 462. Also is known as Socket A,
http://en.wikipedia.org/wiki/Socket_AThe Socket A, or also known as Socket 462, is for AMD processors - Only.Scrolling back up the page we see what CPU's (Processors), are supported.Look to the right of the heading - CPULook at what maximum approved processors, are supported, under the heading - Maximum approved processors:The maximum, or best, CPU your motherboard will support, is an AMD Athlon XP 3200+.The one model that is based on the Barton Core, and has a Front Side Bus of 400MegaHertz. (FSB = 400MHz)
http://en.wikipedia.org/wiki/List_of_AMD_Athlon_XP_microprocessors#Athlon_XP_.22Barton.22_.28Model_10.2C_130_nm.29Look down on the left side until you arrive at - Athlon XP 3200+,and go across to the Part Number - AXDA3200DKV4EThis is the best Athlon XP 3200+Why?You'll notice that the frequency rate ('Speed'), is higher for the Part Number AXDA3200DKV4D model.2333MegaHertz. (Can also be stated as 2.3GigaHertz. It is rounded off. 2.3GHz)However look at the Front Side Bus 'speed'. (Frequency Rate)It's 333MHz for the AXDA3200KV4D.Although the frequency rate for the KV4E is lower, the FSB is higher.400MHz.Think of the Front Side Bus (FSB) as being an 'Information Highway'.It transfers information from the Processor (CPU), to the Northbridge chip. (And vice-versa)The faster a frequency rate the FSB can operate at, means the more information it will be able to transfer back, and forth.Crude example a 4 lane highway to a 2 lane highway. Which will transfer traffic back, and forth at a larger rate?The increase in FSB frequency rate, from 333MHz to 400MHz, makes a BIG difference.Increase in the Processor's frequency rate of 133MHz, (2200MHz to 2333MHz), means Nada.Not enough to write home to Mom about. Now,............finding one of these babies on the market.[ Chip and Chipset are slang terms for I.C.Integrated Circuit,
http://en.wikipedia.org/wiki/Integrated_circuitMotherboard Chipset = Northbridge chip, and Southbridge chip(For the technology used for your motherboard. Does not apply to motherboards that support Intel Core i3, i5, i7, and i9 processors){The Northbridge chip, and the Southbridge chip, are so aptly named because of their locations, on the motherboard.Computer case open, your motherboard can be looked at as, a map on a wall.North to the top, South to the bottom. Front and back, no east/west.The Northbridge chip sits under the processor. (That is, to the South)The Southbridge chip is usually located towards the bottom of the motherboard, or to the South }The Northbridge chip handles the faster capabilities of the computer.The Processor, Ram Memory, and High-speed graphics.{Note*Integrated Graphics, and a graphics card inserted into a PCI slot, (Or connected to a PCI bus), is Not High-speed graphics.AGP technology, and the PCI-Express (X16) technology, is }(PCI-Express x16 for graphics card, not PCI-Express x1)The Southbridge chip handles the slower capabilities of a computer.1) Anything connected to the PCI bus, (As a graphics card in a white PCI slot, for one example), 2) Integrated Graphics. (Integrated graphics is also known as OnBoard graphics. ON the motherBOARD. The GPU is soldered to the motherboard)3) The IDE (PATA) bus, SATA bus, USB bus, Ethernet, and Audio. (Sound)
http://en.wikipedia.org/wiki/File:Motherboard_diagram.svghttp://www.via.com.tw/en/products/chipsets/k7-series/km400a/Regards,joecoolvette
