Hello! So i have a question for updating with a small budget
Motherboard: Asus P5Q-E
Processor: Intel Core 2 Quad Q8400 @ 2.66 ghz
Graphics card: ATI HD 4890
I would like to update the computers performance with a small budget, and i would like to buy another HD 4890 for crossfire, but the motherboard supports only pci-e 8x in crossfire, so should i update something else or just go for the crossfire?
I found this:
HD 4890 = 975mhz (quad piped - 3.9 GB/s data rate) = 3.9 GB/s total data rate
HD 4870 X2 = 900mhz (quad piped - 3.6 GB/s data rate)(times 2) = 7.2 GB/s total data rate
So as you can see, the 4870 X2 will be hurt in an 8X condition and why the 3870, 4650, 4670, 4770, 4830, 4850, 4870, 4890, and 4850 X2 will not be hurt in performance at all.
To upgrade your system without spending much, yes- a decent aftermarket cooler for your CPU would help a bit for not too much money (you can get a good one for ~$30-50).
Crossfiring 4890's ought to be just fine in an 8x/8x PCI-e configuration, and would vastly improve your graphics performance. However- what PSU are you using? The 4890 uses a decent bit of power and you want to make sure your PSU can handle it. You'll need a good quality (good brand) PSU in the 650W+ range with plenty of Amps on the +12V rail.
Overclocking your CPU will give you the best bang for your buck The Q8400 should have no problem of getting to 3.4 3.6GHZ on that motherboard. So find yourself a decent cooler shouldn't have to spend more then 40 to get a nice one. Since you didnt mention your power supply putting a second 4890 in your system could get costly because you will need a good power supply to run 2 of them 650watt min with a Antec, or corsair.
The mobo you have utilizes a P45 chipset so you have PCIe 2.0.
That being said, that means that even at dual x8 PCIe 2.0, you wont notice a performance hit.
If you went with a 4870X2, it would not run in x8 if you got just one. It would run in x16. If you got another HD4890, it would not suffer much more than 3% compared to a dual x16 CF setup.
SO in short, if you get another HD4890 you will be fine. That or just get a single HD 5870, sell the other HD4890 to make up for some of the cost and you will have a single GPU with the performance of a HD4870X2 that uses less power and can run on a full x16 PCIe 2.0 slot.
If you went with another 4890 for crossfire, you would need a better power supply, if you went with a 4870x2, you would need a batter power supply. For both of the above setups, you would want at least a 650w power supply with 45amps on the 12v rail from a reputable brand like Antec or Corsair or Seasonic.
Depending on the power supply you have now, you might be able to get a 5850 or 5870 and be safe. Please list what brand & model # of the power supply you have.
as for going crossfire, you would not see a noticeable difference with 8x 8x, the difference with 8x 8x would only be seen in extreme high-end cards such as 5970 or perhaps GTX295.
Also, that Antec cooler you have for your CPU should be just fine for overclocking to 3.2-ish. when overclocking, start here...
The Thermalright Ultra-120 eXtreme Rev C does have an LGA 1366 bolt-thru retention system- you might just want to make sure you buy one that has it included, but that is one of the best coolers available right now, short of moving to liquid cooling.
True a 500W PSU is not gonna be enough for 2 4890s, so it could get expensive, but its something to think about for the future if you start really getting to a point where you aren't getting the frame rates you want. Also, If you watch for deals on PSU's, you can get a decent one that will power 2 4890s for a good bit under $100 (I got my 750W PSU that would easily power them for ~$80).
Good luck with a new cooler and happy OCing! Its a fun thing to do anyway, plus it makes your PC faster:-)
I don't know the difference between those two, but YES you will want a fan attached. You do not want to be doing any overclocking with just the cooler on there. Both of those coolers are probably fine though as long as you get a 120mm fan on there.