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rohan
June 3rd, 2010, 21:54
I'm looking to buy a new computer which will be used mostly for flight simulation (CFS2, FS9, FSX (Tongass and PNW) and Orbiter), photo editing and database development. In general terms, I'm thinking along these lines - i7-860 to i7-930, air cooling, 8 Gb memory, Velociraptor discs, HD58n0 or GTX 275 (a quiet graphics card under load is as important as performance) and Win7Pro 64 bit in XP Emulation mode. All the suppliers I've looked at like to overclock their builds, though will leave them at stock values if the customer wants.

Recently, I've read a few reviews which have said that there is a significant consequence to more potent overclocking - power consumption. That has lead me to wonder to what extent overclocking can be done without increasing the stock voltage or, to be more precise, overclocking that will still deliver some performance benefits. Since this subject isn't usually addressed in the processor review reports (not yet anyway), I thought I'd ask the experts here for their consideration on whether -
a) the above processors can be usefully overclocked without increasing the voltage above the spec value ?
b) there is any point in my investing in new technology like the i7-875 given the above approach ?
c) there is a "best" buy among the processors listed, given that the planned life of this computer is at least five years and I only expect to have to spend extra money on replacing parts that may fail rather than on upgrading components ?

Thanks in advance for any useful, positive contributions,
regards,
Ro

txnetcop
June 4th, 2010, 06:07
WOW there are a lot of "it depends" in this answer. Assuming you buy the i7 875 how high do you need to overclock it? In FSX and the other games you mention 3.5GHz is probably all that is needed and you don't have to raise the voltage much at all with the turbo capability you get from the processor. How much difference in power costs ratio is 15-20watts if even that much is required? The only problem I have with the i7 875 is the fact that there will be no further upgrade beyond that CPU for the 1156 socket boards. You cannot use any of the i7 900 series processors on an 1156 board and the true i7 series boards require triple channel memory as opposed to dual channel for the 1156 socket boards. You also will not be able to upgrade to the six core processors on the 1156 motherboard, at least that is what has leaked out of Intel. While that won't be a major hindrance for a while as most of the games you want to use it for will not benefit much if at all from six core processing. I hope this helps.
Ted

rohan
June 7th, 2010, 22:04
Ted,
thanks for that. If I understand correctly, you're saying that I should get good FSX performance from an i7-875 running at 3.5 GHz and that the cost in power consumption to get that 3.5 GHz should be no more than an extra 20 watts - all based on the assumption that I keep the Turbo facility enabled. That all sounds very reasonable.

If I was to take an i7-930 instead, I assume that the figures of 3.5 GHz and 20 watts would change. If so, could you possibly give me equivalent ball-park figures for this processor, please, just for comparison ?

As I said in my original post, I'm not thinking in terms of an upgrade path, so an i7-875 could just be my ultimate combination of cost and performance, depending on how much it's going to cost here in rip-off Britain of course,
thanks agin,
Ro

txnetcop
June 8th, 2010, 12:21
Ted,
thanks for that. If I understand correctly, you're saying that I should get good FSX performance from an i7-875 running at 3.5 GHz and that the cost in power consumption to get that 3.5 GHz should be no more than an extra 20 watts - all based on the assumption that I keep the Turbo facility enabled. That all sounds very reasonable.

If I was to take an i7-930 instead, I assume that the figures of 3.5 GHz and 20 watts would change. If so, could you possibly give me equivalent ball-park figures for this processor, please, just for comparison ?

As I said in my original post, I'm not thinking in terms of an upgrade path, so an i7-875 could just be my ultimate combination of cost and performance, depending on how much it's going to cost here in rip-off Britain of course,
thanks agin,
Ro

If what you care most about in gaming is FSX, CFS2 and FS9 then the i7Core 875 with a nice top of line motherboard is all you need to do some really great fps. The only reason I like the i7Core 930 and above is that the 1366 board will offer you the ability to upgrade to six core someday in the future. I believe someday we will get a six core capable flight simulator. While FSX did read all six cores we tested it did not seem to make that much difference. As for cost/performance/power consumption ratio the i7 930 runs close to i7 875 as does the i7 960.

3.5Ghz seems to be the magic number for best results and reasonable power consumption. In the case of the i7 875 you don't necessarily have to raise the voltage to accomplish what you want. You will have to raise the voltage on the CPU and memory with a i7 930 but again not much. An extra 15-20 watts isn't worth worrying about.The video cards are the big juice eaters!
Ted