Processor support

[Guest mahiles]

Does/will Mandrake support AMDs new 64-bit desktop processor when it's released in September? Also does anyone know what kind of things I'll also need to upgrade at the same time? I mean motherboard is obvious enough to me but what about other things such as HDD or RAM?

 

Thanks..

[mtweidmann]

Yes and er.. no. The new Athlon64 chip is interesting because unlike Intel's offering it can run both 32bit and 64bit code without any problems. If you run it as a 32bit chip you'll just end up with a faster AthlonXP in effect, its not until you give proper 64bit code that you'll get the full power of the new chip.

 

There are several flavours of Mandrake, i586, PPC, source, and Athlon64. Mandrake released (or at least annouced) that they had a copy of 9.0 compiled for the new Athlons and I guess if they take off Mandrake will port 9.1 and eventually 9.2 as well. In the mean time your could just run an i586 copy.

 

RAM and hard drives should be fine. There is no reason you shouldn't use 32 bit RAM with a 64bit cpu, you'll just suffer a slight performance loss. Mobile phones are normally 32bit, but use 16bit RAM to save money. No doubt there will be 64bit DDR at some point, but you won't have to have it. AMD have put a lot of effort (unlike Intel) into making their 64bit offering backwards compatible to make it easier for customer to make the switch.

 

Sorry for this rather rambling explanation, but I think I covered most of it. Linux Format magazine did a good article on it a while a go.

[aRTee]

To add a bit to what mtweidmann has said:

 

Mandrake released an Opteron distro, compiled for AMD64. I think you can download it from the usual places.

This one should also directly run on Athlon xp-64.

 

The nice thing about Opteron is that there is only linux available (ok, there are windows 64bit betas) at the moment. So no worries whether the mobo chipset is fully supported or not.... ;)

Thanks to AMD for bringing out the platform and MS for being late with 64bit windows.

 

For Athlon 64 it looks like linux will be the first to have all that is needed to use a 64bit OS; with FLOSS drivers, just recompile. For windows I don't know, but I think it was mentioned that getting all drivers is the big problem; the OS itself is said to function well.

 

BTW you can always just run x86 versions on athlon 64/opteron, since it is fully backwards compatible. The cpu just needs another mainboard.

[mtweidmann]

It wouldn however be a shame to run a 32bit OS on one as you'd miss out on all the benefits of 64bit. Anyone know when the desktop/workstation versions are due for release?

[aRTee]

What are the 64bit benefits really? I don't have more than 1GB of ram, few people have more than 4GB which is the 32bit limit.

 

The other advantages like the new registers will be a bigger miss, but one of the real goodies of Hammer (opteron/athlon64) is the onboard memory controller and large cache. Low latency etc.

 

But I agree, if you can, run a real 64 bit OS on that thing, and make it fly!

 

Thanks to AMD for bringing 64bit (and the rest) to the masses! Well, soon anyway, I hear September 22 for the desktop/workstation AND LAPTOP 64 bit hammer cpu's!

[mtweidmann]

The benefit you see from 64bit depends on what you use your machine for. But the arguements are the same whether for moving from 8 to 16bits or 16bits to 32 bits. They go something like this:

 

- You can address for more memory. Not a huge advantage on a desktop, but a god send to servers. Plus about 10yrs ago (give or take) I got my first PC a 386 with 4MB of RAM. In a decade thats risen to 512MB, so how long until it reaches 4gig?

 

- They shift more data. For every cycle a 64bit core shifts TWICE the data compared to a 32bit core.

 

- You can represent much bigger number more easily. Very useful for maths intensive work.

 

- You can build much stronger encryption.

 

- You have a much bigger potential instruction set.

 

So why didn't we always have 64bits? Hell why not 128 or 256bits?

Same answer (kind of) to both questions. The more bits the more complex the design, and hence the more expensive in over all terms. You have to weigh the gained performance against the extra cost.

 

10yrs ago most people probably wouldn't have got any real performance gain from swtiching to 64bit. But now we puch even our desktops much more and the added performance is worth the cost to some people. Equally we haven't yet reached the point where the jump to 128bits is needed.

 

Its the same for other types of computers. Take mobiles, a lot of the originals were 16bit now they are vitaully all 32bit ARMs. Theres no way you'd fit more than 4gig of RAM into a mobile so don't expect to see 64bit turning up any time soon.

[Sarissi]

64 bit processors have been around for a while now: on mainframes. Now that they are finding their way into non-government commodity market, I would speculate that 128 bit or better CPUs powered mainframes are finding their way into the government arena.

 

The axiom that was around before personal computers is:

 

If it is on the market, it is obsolete. (this is in the computing arena)

 

It holds true, even in personal computers.

[Gowator]

Sorry, Im lazy so Ill just play Devils advocate with mtweidmans post :D

Actually I agree with him, its just such a complex question ....

 

 

The benefit you see from 64bit depends on what you use your machine for.  But the arguements are the same whether for moving from 8 to 16bits or 16bits to 32 bits.  They go something like this:

 

- You can address for more memory.  Not a huge advantage on a desktop, but a god send to servers.  Plus about 10yrs ago (give or take) I got my first PC a 386 with 4MB of RAM.  In a decade thats risen to 512MB, so how long until it reaches 4gig?

 

But your 386 WAS 32 bit.  Only other limitations and the fact no-one could conceive 4GB RAM were preventing it.....

- They shift more data.  For every cycle a 64bit core shifts TWICE the data compared to a 32bit core.

 

Excluding dependency bubbles- You can't do two 32bit fp calculations simulataneously if the input of one depends on the output of the other.  And if your using floating point then the chance is the calculation is a part of a series.  Given that the CISC instruction set can't actually do fp math (definitively) this is a mixed blessing.  In a way the CISC processor has to repeat the same calculation three times and average wheras a RISC will do it in a single pass.  This allows two of the 3 calculations to procede simulataneously .....   This is an inherent weakness of CISC.... the answer is to throw more clock cycles and/or simultaneous calculations or use lower precision.  

 

- You can represent much bigger number more easily.  Very useful for maths intensive work.

This is fairly limited.  We also defeat the two simulaneous 32bit calcs...

- You can build much stronger encryption.

 

- You have a much bigger potential instruction set.

Hmmm.  Good or bad.... SGI and MAC seem to manage much better performance with a RISC instruction set.  

 

So why didn't we always have 64bits?  Hell why not 128 or 256bits?

Same answer (kind of) to both questions.  The more bits the more complex the design, and hence the more expensive in over all terms.  You have to weigh the gained performance against the extra cost.

 

Hmm but CISC is already inherently more complex, 62 bit RISC has been around for a while.... I think its a combination.... The RISC method is throw in higher revs on a smaller engine...(European/Japanese sports car). Whereas the CISC method is putting in a more powerful engine (V12) that can be made more cheaply for its size becuase its simpler.  

The Turbo-charged CISC relies on lots of peripheral technology, high revs etc to achive a power.  The enginerring must be perfect to get 12,000 rpm without the engine blowing up.  Honda finish all type-R engines by hand.  

The RISC engine can be manufactuered a lot less stringently becuase it is much simpler.  IT develops the same power at much lower revs so it doesn't need the hand finishing of a Honda type-R engine.    

 

But which is better ......

Who knows or cares....

Japan and Europe signed up to Kyoto and making inefficient V12's that pour out pollution isn't an option for them.  Even European V12's are much more emmision friendly (and much more expensive) than a US V12.  So the interesting comparison breaks down becuase European/Japanese manufactuers don't actually have an option of producing the cheap V12..... Oh well....

 

10yrs ago most people probably wouldn't have got any real performance gain from swtiching to 64bit.  But now we puch even our desktops much more and the added performance is worth the cost to some people.  Equally we haven't yet reached the point where the jump to 128bits is needed.

 

Hmmm.  The new graphics chipsets are running 256 bit.... albeit RISC....

Its the same for other types of computers.  Take mobiles, a lot of the originals were 16bit now they are vitaully all 32bit ARMs.  Theres no way you'd fit more than 4gig of RAM into a mobile so don't expect to see 64bit turning up any time soon.

4GB RAM.... in a mobile, why not....

I walked into a consumer store the other month and saw a 1GB compact flash... heck 5 years ago 4MB was extravagant....

Given that progression ... I don't see 4GB as unachievable...it will certainly allow more DivX recording on your phone.