Opterons - help me suss the madness!!

stealthgeek

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Hi

I recently started looking for an upgarde CPU for my aging Barton 2500 OC to 3200 - I was in 2 minds about getting an X2 4200 or just go for the pure brute-force of a 64 4000.

That was until I stumbled across a post regarding Opterons...

It seems that I can get an Opteron 146 for about £150 and overlcock it to at least 2.8Ghz, 800 Mhz over its stock speed! I was ready to buy it when I saw another post on here recommending the Opteron 165 for the same reason, but this time it has two cores! So I have found one of these available for about £220

my question is - which is better?? I mainly play games, but also occasionally do some encoding etc, so dual cores would be nice, but does the performance increase warrant the extra £££?

ALSO, and very importantly, will the Gigabyte GA-K8V Ultra-939 be OK for this type of overclocking? Judging from their CPU compatibility list, both Opterons are supported with a BIOS flash, but I didnt know if they would handle such extreme OC's on this board. I HAVE to have this board as I have only recently upgraded to an AGP x800 Pro (which is OC'd to X800 XT with 16 pipelines) , so I dont really want to shell out extra for a new GPU.

Just for info - my system spec is:

AMD Athlon XP 3200 @ 190FSB
3 x 512MB Crucial DDR
Sapphire X800 XT Toxic Edition
Asus A7N8X-E Deluxe
Elan Vital Greenerger Silent 450W PSU (check quietpc.co.uk for details)
4 x hard drives (2 x 120GB SATA in RAID 0, 1 x 300GB SATA, 1 x 120GB PATA)
2 x 120MM dustproof fans
D-Link 108Mb wireless PCI
Hauppage WinTV Nova-T PCI
SIL 3112 SATA controller PCI
Soundblaster Audigy 2 ZS PCI
 
I'd indeed go for the dual core Opty 165...

many are ocing on older Gigabyte NF3 boards, and they are nearly as fast on average as NF4 boards, and some are faster.

Even if it wouldnt OC at all (doubtful), it would still be faster than an XP/NF2 rig by far....; a 400 Mhz OC should be easily obtainable
 

luminaris

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I don't think so. You should be fine with that RAM. The only thing that might hamper it a little is the fact that you've got three modules.
 

stealthgeek

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I just checked the manual for the GA K8V Ultra - it says that in the BIOS you can set the multiplier between 4 and 20 (800-4000Mhz) and you can set the CPU external clock from 200 to 255. Does this mean I will get a crappy 250Mhz OC (9 x 250)?? If so, theres not much point getting it!
 

penguin_d

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If you get a 170, the multiplier is X10 so you can hit 255oMHz at the top end of the board which is faster than the X2 4200+

You may want to consider droping 1 stick of ram (I know that sounds ubsurd) but the timings and such will be much easier to set up with 2 sticks than 3.

An opteron will be my next proc as well.. just waiting on the $$'s to do it.
 

luminaris

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The multipliers for opterons are locked. Mine is locked at 9X so I can't go any higher. That doesn't mean you can't OC the crap out of it though.
 

luminaris

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No your not screwed at all. OC'ing is a skill and you use the tools given to you to do it. The opterons OC much better than their counterparts. My 165 is currently running at 2.4Ghz and is rock solid stable.
 

stealthgeek

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But if the multiplier is locked at 9 and the maximum FSB is 255, then the maximum clock speed will be 2295! How do I get above that?
 

stealthgeek

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Im sure it will OC madly, but with my choice of board, its just not going to be possible with the 255 FSB limit. I have looked around for other socket 939/AGP boards and everything else seems a lot worse than this! I might just go ahead with it anyway - at least furhter down the line when I ugrade to PCIe/NF4 it will unlock its true potential
 

unsmart

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Can you drop the mem speed in bios to 166? Have you looked for a bios hack or mod. If you set the fsb to 166 you can get 440mh[ 44x10] oc before you even hit 200. I'm not sure on your board but theres alot of mod bios out there.
there are boards out with agp and pcie, the price is low on them not sure on the performance.
 

stealthgeek

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Well thanks to a tasty pay rise, I wont have to find out! I bought an Opteron 165 yesterday, and plan on getting the new DFI Crossfire board wih an x1900!

The stepping is CCBWE 0551 VPMW and apparently it can reach 2.7 on air - shall wait and see...
 

andelero

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I'm also trying to decide between the 165 and the X2 3800+. I've followed the OC discussion here and elsewhere (I'm apparently not the first with this dilemma!) regarding these CPUs and I'm still a bit confused.

I'm not even sure I'm going to OC (building my first, we'll see how it goes) but let's assume that when I do, I want to do it with the stock cooling, and no voltage tweaks.

Ok, my understanding is that the 3800 can also be OCed into the 2700-2800 range. If I were to adhere to the requirements stated could I get it to say 2400?

If I were happy with, say, 2400 from either the 165 or the 3800, then is there any other reason I would pay 10% more for the 165? Where is the value in spending the extra money if both CPUs end up at the same point?

I know the 165 has the bigger L2, but from the benchmarks I've seen, it doesn't seem to matter much except for games. I will play some, but the difference between 155 and 160 fps isn't a concern.

So, I guess it boils down to this. If both chips are OC'ed to their "safe" limit (no special cooling or voltage), is the 165 still the best choice at $330 compared to the 3800 at $295?

Thanks!
 

stealthgeek

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Wow your'e building your first rig and your'e going for an Operon or x2?! Thats impressive! Good luck with that :)

I think the consensus is that the only plus going for the Opteron over the x2 is the overclock-ability. If your'e not planning on overclocking much or playing games etc, then theres not much point wasting the cash. Add to this that the Opteron is not officiallly supported on some boards (DFI for sure), then you really are taking a risk for not very much in return!