You may want to check the memory forums at places like
www.overclockers.com,
www.hardOCP.com,
www.tomshardware.com, etc.
I've heard good things about TwinMOS but have no experience with hit.
My track record with budget Kingston modules hasn't been good. One of
their 256MB PC2100 modules failed testing, and a whopping 8 out of 11
or 12 of their 512MB PC3200 modules failed. Also bad was a 512MB
PC3200 Mushkin whose SPD said was a Kingston. OTOH the 1GB PC5300
DDR2 modules I bought a few months ago were fine, even when
overclocked.
I've never heard of Supertalent, but I bought my first heatsinked
memory a few days ago, a matched pair of 1GB OCZ Gold PC6400 modules.
Their heatsinks are nothing but a nuisance, and one of the modules
showed a few bad spots, always in the 26th bit, whether run alone or
with the other module. The next pair I tried had a much worse module
that made the computer beep-beep-beep on boot, every time when run
with the other module, half the time when run alone. But the third
pair of OCZ modules have so far passed all diagnostics. BTW, each
time I went to the store to exchange the bad OCZ, I saw a customer
trying to return some, too.
Can you buy Crucial memory? Because it's about the only retail memory
that always comes with good chips, either Micron (Micron owns Crucial)
or Samsung. Almost every other brand is made with untested chips (UTT
-- a search will return horror stories).
The diagnostics I use are from
www.MemTest86.com (but MemTest+, from
www.MemTest.org, is very, very similar) and Gold Memory ver. 5.07 from
www.GoldMemory.cz. Both were highly praised in a review by
www.RealWorldTech.com, but I found that newer versions of Gold Memory
weren't nearly as good at finding errors. I ran each program
overnight or until errors were reported, whichever came first. I run
both programs because some modules have passed one of these
diagnostics but failed the other.