1333 mobo and 1600 CPU...?

[dumpystig]

Can't find a definitive answer - will my 1333 FSB mobo run a 1600 FSB CPU?

[joshnz]

Re: 1333 mobo and 1600 CPU...?

My guess is the CPU FSB is been run at 1333 instead of 1600.
If my knowledge is correct the CPU's clock source is from the chipset.
So the CPU FSB is limited by that. the CPU still can run at xGHz due to the multiplier.

[ratdude747]

Re: 1333 mobo and 1600 CPU...?

(delete this, i realized he was talking speeds not sockets)

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

So that's a yes then?

Scenario:

Mobo rated at 1333 FSB.

Choice of 2 different processors, at similar prices.

CPU #1 - E5450 @ 1300 FSB
CPU #2 - E5472 @ 1600 FSB

CPU #1 is listed for this board and is therefore compatable.
CPU #2 has higher FSB than mobo - would it work, and would there be any point or would it be wasted? (I think this is a slightly better CPU than CPU #1...?)

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

ratty

[joshnz]

Re: 1333 mobo and 1600 CPU...?

It is a yes but if the CPU costs more it is a waste.
Also you may not get x GHz from the CPU.

[ratdude747]

Re: 1333 mobo and 1600 CPU...?

ratty

we all screw up once in a while

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

Thanks joshnz, you've sort of helped but I'm going to wait and see if anyone else has any thoughts on this. It may be a simple q/a to some people but TBH it's got me stumped.

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

we all screw up once in a while

I have a knack...

[shovenose]

Re: 1333 mobo and 1600 CPU...?

Use The 1333 one. It might actually run at a higher ghz than the 1600.

[joshnz]

Re: 1333 mobo and 1600 CPU...?

CPU #1 is listed for this board and is therefore compatable.

I would recommend this CPU.

CPU #2 has higher FSB than mobo - would it work, and would there be any point or would it be wasted?

This CPU would be wasted due to you will not get the bonus of the extra memory bandwidth.
That is the reason your board is not listed.
According to Intel's site these are identical except for the FSB.

CPU 1 http://ark.intel.com/products/33083/...z-1333-MHz-FSB)
CPU 2 http://ark.intel.com/products/33085/...z-1600-MHz-FSB)

[brethin]

Re: 1333 mobo and 1600 CPU...?

Can't find a definitive answer - will my 1333 FSB mobo run a 1600 FSB CPU?

Might help if you said what MB you have make/model. Otherwise its like asking if the wife will spit or swallow, it depends on her make/model. :P

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

Hmm... I didn't think the mobo manufacturer would make any difference, but it's original HP xw6600. And last time, she swallowed

I've done the comparison, only differences are FSB and Bus/Core Ratio.

Thing is, I may be able to get 2x E5472 for less than 2x E5450 - I don't think I was clear about that earlier.

But nobody has really given a good answer yet...
Got you buggers thinking tho'

[brethin]

Re: 1333 mobo and 1600 CPU...?

Mobo Manufacturer matters alot esp Dell/HP etc they block/limit everything they sell. HP xx6600 means shit you might have well said 6" blond. Unless you have more details about the motherboard you are on your own.

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

Yes, well unfortunately your only comments on this thread mean about the same, and are just as pointless, but thanks for trying anyway.

I found this:

•Going with a 1333 MHz chip on a 1066 board? Not good. At best, the board will run the CPU slower than it's rated -- baring some serious overclocking. At worse, the whole setup will fail and refuse to boot. There's a lot of other scenarios and variables here in play, too. Don't do it.

[Spitz]

Re: 1333 mobo and 1600 CPU...?

Hmm... I didn't think the mobo manufacturer would make any difference, but it's original HP xw6600.
I've done the comparison, only differences are FSB and Bus/Core Ratio.
But nobody has really given a good answer yet...
Got you buggers thinking tho'

Yes it will run the 1600 cpu but only at the 1333 speed. You will not get the full benefit of the faster cpu. Just for information: In the electronics world, they do not make all the different speed chips. They try to make the faster ones which they test to see what speed it can run reliable at. It is then marked for that speed. This is true of memory chips, cpu, chipsets, etc. Sometimes they will actually mark a chip at a lower speed than it tests to meet a large order. Thats why over-clocking works.

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

OK, so I've gleaned some extra info, but still looking for a more definitive answer so all help is welcome.

My mobo (HP xw6600 workstation) is rated for both 1333 and 1600 Bus speeds. According to HP Tech Support HP BIOS apparently limits my mobo to 1333, 1600 is 'locked out', i.e. will not work. I would like to install 2x CPU which are rated @ 1600.

As far as I can see there could be two main outcomes:

A/ BIOS prevents operation/boot. System inoperable because of incompatability between BIOS and CPU.
B/ BIOS allows operation/boot. System runs normally, but CPU runs @ 1333 instead of 1600.

Can anyone tell me with a considerable amount of certainty (90%?) if the second outcome is a good probability, and that the setup will run, albeit with the CPU at 1333 instead of 1600?

I have a chance to get 2x E5472 cheaper than E5450's or even E5420's, hence me trying to find an answer. If it works I'm not too worried about reduced bandwidth and the E5472's @1333.

[b700029]

Re: 1333 mobo and 1600 CPU...?

According to HP Tech Support HP BIOS apparently limits my mobo to 1333, 1600 is 'locked out', i.e. will not work.

That means the hardware is rated for 1600, now all you need is a BIOS mod to get it up there.

Try asking these guys: http://bios-mods.com/forum/

[dumpystig]

Re: 1333 mobo and 1600 CPU...?

Yeah, I already said that the mobo/chipset will support 1600 - it's just the pita HP BIOS that may be the stumbling block. I've just had a look at the link you gave, and I ain't got a clue where to even post a request...

[mariushm]

Re: 1333 mobo and 1600 CPU...?

I wouldn't risk getting the processor with 1600 Mhz bus - the bios may have a hardcoded list of processor ID codes and reject everything outside that list.

With any other motherboard, the processor should at least run at "degraded" speed of 1333 Mhz but if the HP people disabled 1600 Mhz in the Bios who knows what else they disabled/locked...

ps according to cpubenchmark.net the performance is almost identical (e5472 and e5450) but yes, the price...