hi,

my pc is old, so i want to buy a new one. can any one tel me which one is best to practice LINUX virtualisation. AMD phenom 2 x2 550/555, and which mother board makes it best. Please help me i'm really unable to sort it out.

thank you very much,

The only difference between a X2 550 and a X2 555 is 100MHz.

X2 550 = 3.1Ghz.
X2 555 = 3.2Ghz.

Unless you are planning on overclocking, or unlocking cores, there isnt a huge amount of differences between motherboards. I'd still try to get a quailty board though, they tend to last longer and be a bit more stable.

At least here, the price difference between those two is almost negligible, so it really shouldn't be all that difficult to choose (and, by the way, that information should have been available to you with a simple search, so what is published here it probably shouldn't have changed your approach all that much).

So, it is all easy, if that is your only choice, but it probably isn't. Again, here, at least, something like a Ph II X4 isn't vastly more expensive, and offers twice the number of cores (may still be outside your budget, though, and on that I can't comment). And a FX-4100 isn't much more either, so if those parts are within your budget, consider whether having more cores for not much more expense is the kind of thing that you'd want; it probably doesn't help virt directly, but you could have applications in which more cores are better, it is difficult to tell.

Regarding motherboards, ensure that you have a look at the prices of AM3+ boards on your market - AM3+ would give you the option of upgrading to, eg, a FX-4110 (or even more cores) later, but the prices of available boards here tend to be towards the upper end of the spectrum (from a general purpose, rather than 'gamers' board perspective), so while AM3+ may be desirable, the price might be inconvenient, if the local dealers have only got upper end boards for sale.

thanks for your response. i'm thinking about overclocking so i'll opt phenom x2 555. As you said no need to worry abt boards unless i go for overclock, but since i want to overclock, plz tel me the good ones support overclock. ASUS,GYGABYTE, etc. shouldn't be more expensive.

by the way is any thing going to be wrong if i over clock it.

thank you.

Well, overclocking is always going to be at your own risk; most people who are experienced overclockers have absolutely no problem with overclocking, but than they are experienced overclockers. If I was intending overclocking (which is quite unlikely for anything that I was doing serious work on, as opposed to gaming) then I would want to be sure that cooling was good. In any case, I'd want to use a better cpu heatsink/fan combo than the standard manufacturer-supplied items, for the usual two reasons (noise, temperature), but, for many people, only one of those will be important.

for the last few day's i'm really wasting my time in comparing processors today i lost my temper, old pc is testing my patience. Let's sort it out please help me.
*****************
1. AMD Phenom™ II X2 560
3.3 Ghz
6MB L3 cache
2 cores (4cores if unlocked)
*******************************
AMD Athlon II X4

3.0 Ghz
2MB Cache, No L3 Cache
4 Cores
********************

Athlon Quad core has 4 cores but no L3 Cache,
Phenom dual core has 2 cores but has 6MB of L3 Cache. Other unlocking 2 cores is my luck.

MY doubt is what should i prefer 6MB L3, or 4 cores in athlon. Ofcourse we can unlock Phenom to 4 cores, if do so any problem in future. What should be the features i should check before buying mother board for Phenom to unlock cores.
what are the mother boards available for unlocking.
#########################
is 6MB L3 igonable for 4 cores in the Athlon, is Quad core by default better than over clocked Phenom.
#########################
Please tel me which one from above is best and safe, i don't want to waste time.

PLEASE ANY ONE HELP ME CLOSE THIS ISSUE FAST

THANK YOU VERY MUCH IN ADVANCE.

Having a look all the questions you ask I doubt that overclocking is a reasonable thing to do for you at this time. You seem to lack the knowledge needed for overclocking when you even don't know which CPU and motherboard you should buy.

To you questions:
This highly depends on the workload you intend to run on that machine. Single threaded software will run faster on a highly overclocked dual-core than on a standard clocked quad-core. But if you are running multithreaded software you will never beat the quad-core with a dual-core.
The best option would be to go for a Phenom 2 X4 or X6 or one of the new AMD FX processors and overclock that.

That is easy, look for a board that supports core unlocking. I looked around for a board for overclocking my Phenom 2 X6 (just for the fun of it) and came to the conclusion that I will go for the ASUS M5A99X Evo, should be around 150$.

If you get a 'good' Phenom II X2, have a good motherboard and decent cooling, a X2 5XX unlocked to X4 is pretty stable.

A few problems with that though, the good overclocking motherboards are more expensive, you have no idea how well any CPU will unlcok/overclock untill you have tried it, and its a very good idea to buy an aftermarket cooler (the stock heatsink can work with unlocked X2s, but its more risky than a better aftermarket CPU heatsink).

Since you seem to be looking at the cheapest Phenom II X2s and Athlon X4s, I would guess that you dont have much money to spare? Buy a Athlon II X4. Overclocking _anything_ is a risk, and can lead to CPU and motherboard damage. Dont risk it unless you can afford to replace parts.

Sorry, but for many people, going beyond two cores isn't of all that much value, but I can't really tell whether you are one of those people. I just don't know enough about your workload.

@TobiSGD
I agree with that absolutely, but, there is a possibility that the OP is short of the cash needed to do this properly and will learn about overclocking later. OTOH, there is also the possibility that we'll get an 'urgent...overclock my PC for me...' thread later, which would be a unhelpful. You should also note that there are no guarantees with core unlocking, in the same way that there are no guarantees with overclocking, in general.

Assuming that what you tell us is correct, the bottom line here is that whatever you buy today will be faster than your old PC. To quote Carrol Shelby "Speed costs...how much do you want to go?". Well, how much do you want to go, and how much are you prepared to spend to get there (not that the amount of money will help anyone who is unfamiliar with the market conditions local to you)?

Exactly that is my point. Overclocking without having the needed knowledge will most likely end in an unstable or even dead machine. While you can fix the instability issues with simply going back to clock speeds, you can't do that if you have fried your hardware. Therefore, especially when you are short on money, overclocking is not really the way to go, just because 1. even the best overclocker will eventually fry his hardware (he just doesn't care and buys new stuff), and 2. you will void your warranty, even if the machine dies from failures not caused by overclocking. That means you have to buy new stuff when something dies to make your computer run again, you can't rely on the warranties.

So there are two ways to go, I would think, if you need more power than you can afford:
1. Read up all you can about overclocking, especially the part of overclocking your specific CPU. Read up which motherboards are good to overclock that specific CPU. Try to understand that stuff, if you don't get it then ask, there are many people out there in overclocker forums that will help you. Be aware that none of those parts (motherboard, CPU) have a guaranteed overclocking capability. Then go and buy those things and try to overclock them, using your gathered knowledge.
2. Don't buy the computer now, save more money and then buy a more powerful computer. May be buy a used machine.

first of all your time. As you said i'll go for Athlon Quad core or i simply go for phenom with out unlocking cores. You still didn't clarified my doubt, ahtlon has quad core, phoenom has 6Mb L3 cache whichi is not present in athlon. I run kvm's and do parallel tasks a lot. so quad core without L3 cache or phenom dual core with 6Mb L3. Please tell me. sorry for asking the same thing again and again.

thank you very much.

The L3 cache is used for speeding up access to data and instructions that otherwise have to be read from RAM. But it will not outperformance two extra cores when you run multithreaded software. When it is up to virtual machines I would definitely go for the quad-core.